President Vladimir Putin has delivered a chilling warning to Russian "traitors", describing them as a "fifth column" being used by the West to destroy Russia. 

He attacked Russians who he said had mentally aligned themselves with the West, and said the Russian people could discern between traitors and patriots, describing the former as "scum." 

"Of course they (the West) will try to bet on the so-called fifth column, on traitors - on those who earn their money here, but live over there. Live, not in the geographical sense, but in the sense of their thoughts, their slavish thinking," he told government ministers. 

"Any people, and especially the Russian people, will always be able to distinguish the true patriots from the scum and the traitors, and just to spit them out like a midge that accidentally flew into their mouths." 

Slovakia could give defence system to Ukraine 

Slovakian defense officials expect to discuss a possible transfer of their Soviet-era S-300 air defense systems to Ukraine when U.S. Defense Secretary Lloyd Austin visits there Thursday, a Slovak military spokesperson said. 

Ukrainian President Volodymyr Zelenskyy mentioned the S-300s by name when he spoke to U.S. lawmakers by video Wednesday, appealing for anti-air systems that would allow Ukraine to "close the skies" to Russian warplanes and missiles. 

Slovak Defense Ministry spokesperson Martina Koval Kakascikova said Slovaks expect the issue to be on the agenda when Austin comes to Bratislava for talks. 

Slovakia has no objections to providing its S-300s to Ukraine, she said. "But we can't get rid of a system that protects our air space if we don't have any replacement." 

The S-300s use long-range missiles that are capable of flying hundreds of miles and knocking down cruise missiles as well as warplanes. The Soviet-era anti-air defense systems could be valuable in thwarting Russian air attacks on cities and other targets. 

U.S. President Joe Biden said Wednesday that the U.S. would help provide long-range air defense systems to Ukraine, but gave no details. U.S. officials had no comment on any S-300 swap. Three NATO members — Slovakia, Greece and Bulgaria — are reported to have S-300s. 

Attack in Mariupol 

Video has emerged from the city of Mariupol showing a theatre levelled by a Russian bomb. The building was being used by hundreds of locals as a shelter. 

Mariupol's city council has claimed in a statement: "It is still impossible to estimate the scale of this horrific and inhumane act." 

Ukraine's foreign minister Dmytro Kuleba wrote on Twitter, "Russians could not have not known this was a civilian shelter." 

Ukraine's parliament said that rescuers could not reach the scene due to intense fighting. "Now there are fierce battles. No one can reach the blockages, we don't know if there are any survivors," they wrote on Twitter. 

The council claimed that the central part of the theatre was destroyed, as well as the entrance to the bomb shelter in the building. 

Another city official claimed "more than a thousand people were hiding there" when the building was bombed. 

Biden calls Russian leader Vladimir Putin 'a war criminal' 

President Joe Biden speaks about additional security assistance that his administration will provide to Ukraine in the South Court Auditorium on the White House campus in Washington. Photo / AP 

President Joe Biden on Wednesday called Russian President Vladimir Putin a war criminal as the atrocities in Ukraine mount and the president there begged the U.S. Congress for more help. 

"He's a war criminal," the president said of Putin as he left an unrelated event. It's the sharpest condemnation yet of Putin and Russian actions by a U.S. official since the invasion of Ukraine. 

While other world leaders have used the words, the White House had been hesitant to declare Putin's actions those of a war criminal, saying it was a legal term that required research. 

But in a speech Wednesday, Biden said Russian troops had bombed hospitals and held doctors hostage. He pledged more aid to help Ukraine fight Russia. 

 

US President Joe Biden says America is sending more anti-aircraft, anti-armour weapons and drones to Ukraine to assist in its defence against Russia. 

The President's comments came as he formally announced his administration would send an additional US$800 million in military assistance to Ukraine, making a total of US$2 billion in such aid sent to Kyiv since Biden took office more than a year ago. About US$1b in aid has been sent in just the last week. 

"We're going to give Ukraine the arms to fight and defend themselves through all the difficult days ahead," Biden said. 

Biden spoke hours after Ukrainian President Volodymyr Zelenskyy delivered a video address to members of US Congress in which he made an impassioned plea for the US and West to provide more help to save his young democracy than world leaders have so far pledged to provide. 

Zelenskyy summoned the memory of Pearl Harbour and the September 11, 2001, terror attacks in appealing Wednesday to the US Congress to do more to help Ukraine's fight against Russia, but he acknowledged the no-fly zone he has sought to "close the sky" to airstrikes on his country may not happen. 

Livestreamed into the Capitol complex, Zelenskyy said the US must sanction Russian lawmakers and block imports. 

But rather than an enforced no-fly zone that the White House has resisted, he instead sought other military aid to stop the Russian assault. 

For the first time in a public address to world leaders, he showed a packed auditorium of lawmakers a graphic video of the destruction and devastation his country has suffered in the war, along with heartbreaking scenes of civilian casualties. 

"We need you right now," Zelenskyy said. "I call on you to do more." 

Lawmakers gave him a standing ovation, before and after his short remarks, which Zelenskyy began in Ukrainian through an interpreter but then switched to English in a heartfelt appeal to help end the bloodshed. 

"I see no sense in life if it cannot stop the deaths," he said. 

Ukrainian President Volodymyr Zelenskyy speaks to the U.S. Congress by video to plead for support as his country is besieged by Russian forces, at the Capitol in Washington. Photo / AP 

Nearing the three-week mark in an ever-escalating war, Zelenskyy has used the global stage to implore allied leaders to help stop the Russian invasion of his country. 

The young actor-turned-president often draws from history, giving weight to what have become powerful appearances. 

President Joe Biden's administration has stopped short of providing a no-fly zone or the transfer of military jets from neighbouring Poland as the US seeks to avoid a direct confrontation with nuclear-armed Russia. 

Biden was to deliver his own address following Zelenskyy's speech, and was expected to announce an additional $800 million in security assistance to Ukraine, according to a White House official. 

That would bring the total announced in the past week alone to $1 billion. It includes money for anti-armour and air-defence weapons, according to the official, who was not authorised to comment publicly and spoke on the condition of anonymity. 

The White House is considering giving Ukraine access to US-made Switchblade drones that can fly and strike Russian targets, according to a separate person familiar with the matter who was not authorized to speak publicly. 

Zelenskyy has emerged as a heroic figure at the centre of what many view as the biggest security threat to Europe since World War II. Almost three million refugees have fled Ukraine, the fastest exodus in modern times. 

House Speaker Nancy Pelosi of Calif., walks with Ukraine's Ambassador to the United States Oksana Markarova. Photo / AP 

Wearing his now trademark army green T-shirt, Zelenskyy began the remarks to his "American friends" by invoking the destruction the US suffered in 1941 when Japan bombed the naval base at Pearl Harbour in Hawaii, and the 2001 attacks on the World Trade Centre and the Pentagon. 

"Remember Pearl Harbour? ... Remember September 11?" Zelenskyy asked. "Our countries experience the same every day right now." 

Senator Angus King, the Maine independent. said there was a "collective holding of the breath" in the room during Zelenskyy's address. 

Republican Lisa Murkowski of Alaska said: "If you did not look at that video and feel there is an obligation for not only the United States but the free countries of the world to come together in support of Ukraine, you had your eyes closed." 

Majority Whip Dick Durbin called the address heartbreaking and said, "I'm on board with a blank cheque on sanctions, just whatever we can do to stop this Russian advance." 

Outside the Capitol, demonstrators held a large sign lawmakers saw as they walked back to their offices. "No Fly Zone = World War 3." 

The Ukrainian president is no stranger to Congress, having played a central role in Donald Trump's first impeachment. 

As president, Trump was accused of withholding security aid to Ukraine as he pressured Zelenskyy to dig up dirt on political rival Biden. Zelenskyy spoke Wednesday from a giant screen to many of the same Republican lawmakers who declined to impeach or convict Trump, but are among the bipartisan groundswell in Congress now clamouring for military aid to Ukraine. 

He thanked the American people, saying Ukraine is grateful for the outpouring of support, even as he urged Biden to do more. 

"You are the leader of the nation. I wish you be the leader of the world," he said. "Being the leader of the world means being the leader of peace." 

It was the latest visit as Zelenskyy uses the West's great legislative bodies in his appeals for help, invoking Shakespeare's Hamlet last week at the British House of Commons asking whether Ukraine is "to be or not to be" and appealing to "Dear Justin" as he addressed the Canadian Parliament and Prime Minister Justin Trudeau. 

He often pushes for more help to save his young democracy than world leaders have so far pledged to provide. 

To Congress, he drew on the image of Mt Rushmore and told the lawmakers that people in his country want to live their national dreams just as they do. 

Ukrainian President Volodymyr Zelenskyy delivers a virtual address to Congress by video at the Capitol in Washington. Photo / AP 

"Democracy, independence, freedom." 

Biden has insisted there will be no US troops on the ground in Ukraine and has resisted Zelenskyy's relentless pleas for warplanes as too risky, potentially escalating into a direct confrontation with nuclear-armed Russia. 

"Direct conflict between Nato and Russia is World War III," Biden has said. 

Zelenskyy appeared to acknowledge the political reality. 

"Is this too much to ask to create a no fly zone over Ukraine?" he asked, answering his own question. "If this is too much to ask, we offer an alternative," he said, calling for weapons systems that would help fight Russian aircraft. 

The Biden administration has sent Ukraine more than 600 Stinger missiles, 2600 Javelin anti-armour systems, unmanned aerial system tracking radars, grenade launchers, 200 shotguns, 200 machine guns and nearly 40 million rounds of small arms ammunition, along with helicopters, patrol boats, satellite imagery and body armour, helmets, and other tactical gear, the US official said. 

Congress has approved $13.6b in military and humanitarian aid for Ukraine, and the newly announced security aid will come from that allotment, which is part of a broader bill that Biden signed into law Tuesday. 

'Horrific and inhumane' 

Video has emerged from the city of Mariupol showing a theatre levelled by a Russian bomb. The building was being used by hundreds of locals as a shelter. 

Mariupol's city council has claimed in a statement: "It is still impossible to estimate the scale of this horrific and inhumane act." 

Ukraine's foreign minister Dmytro Kuleba wrote on Twitter, "Russians could not have not known this was a civilian shelter." 

Ukraine's parliament said that rescuers could not reach the scene due to intense fighting. "Now there are fierce battles. No one can reach the blockages, we don't know if there are any survivors," they wrote on Twitter. 

Putin dismisses peace talks as 40k Syrians sign up to fight with Russia 

Three European leaders staged a defiant show of support for Ukraine this week, travelling to its besieged capital, Kyiv, as negotiations faltered and a relentless Russian artillery bombardment left apartment towers in the city ablaze. 

The dramatic visit by the prime ministers of Poland, the Czech Republic and Slovenia, which unfolded in tight secrecy as they crossed the Ukrainian border by train after dawn, was a strikingly personal gesture. 

But it caught other European leaders off guard, angering some and baring uncomfortable divisions in how best to demonstrate Western solidarity with Ukraine. 

It also came as President Vladimir Putin of Russia disparaged the second consecutive day of negotiations with Ukraine, undercutting faint glimmers of hope from talks the day before that both sides were looking for a way to halt the war. 

A spokesperson for Poland's Prime Minister, Mateusz Morawiecki, said the three visitors were "de facto" representing the European Union in Ukraine. In Brussels, however, officials said the trio did not have the EU's blessing, and some European diplomats complained that the trip was too risky, given the Russian forces encircling Kyiv. 

Others said they admired the audacity of the group, which also included Prime Minister Petr Fiala of the Czech Republic and Prime Minister Janez Jansa of Slovenia, casting it as a powerful symbol of the backing for Ukraine among countries on Europe's eastern flank, where the spectre of Russian aggression looms larger than in Paris or London. 

Ukrainian President Volodymyr Zelenskyy speaks during a meeting with prime ministers of Poland, the Czech Republic and Slovenia. Photo / AP 

Still, for all the symbolism of standing shoulder to shoulder with Ukraine's leaders under the threat of Russia's rockets, Ukraine was facing the devastating barrage largely on its own. 

The Mayor of Kyiv, Vitali Klitschko, imposed a 35-hour curfew, which suggested the capital was entering an even more difficult phase of its grinding struggle to hold off Russian troops and tanks. 

"This is their attempt to annihilate the Ukrainian people," Zelenskyy said in an emotional video to the Canadian Parliament, repeating his plea for Nato to enforce a no-fly-zone over the country. 

"It is an attempt to destroy our future, our nation, our character." 

Zelenskyy's language has become more pointed, even scolding, with each speech to a Western audience, revealing his frustration with leaders who have resisted more direct military involvement out of fear that it would entangle them in a wider conflict with Russia. 

Biden is scheduled to fly to Brussels for an extraordinary summit meeting of Nato on March 24. That may result in further economic and military aid for Ukraine but will likely fall short of Zelenskyy's request for a no-fly-zone. 

Administration officials declined to say whether Biden planned to meet the Ukrainian President, whom he has called a hero. But they said Biden may go on to Eastern Europe to meet refugees streaming out of Ukraine. 

The river of people fleeing the war continued unabated yesterday, as Russia claimed to have seized control of the strategic Kherson region in the south. 

An elderly woman is helped by policemen after she was rescued by firefighters from inside her apartment after bombing in Kyiv, Ukraine, on March 15. Photo / AP 

Russian forces kept up their pounding of civilian targets in Kyiv, where Ukrainian troops were fortifying intersections with sandbags, tyres and iron spikes. 

A pre-dawn rain of rockets on Kyiv shattered windows, left craters in buildings and turned a 16-floor apartment house into a towering inferno. The fire spread quickly after a missile struck the building, blowing a jagged hole at its entrance. Firefighters rescued residents from windows by ladder through billowing smoke. By mid-afternoon, they had carried out two bodies. 

A senior US defence official said the Russians were using long-range fire to hit civilian targets inside Kyiv with increasing frequency but their ground forces had little to no progress and were still about 15km from the centre of the capital. 

The official said the US has seen indications that Russia believes it may need more troops or supplies in Ukraine. 

The official did not elaborate, but other Western security sources have said Russia is trying to hire Syrian mercenaries experienced in urban combat. 

A war monitor said yesterday that Russia had drawn up lists from the Syrian Army and allied militia to be put on standby for deployment. 

"More than 40,000 Syrians have registered to fight alongside Russia in Ukraine," said Rami Abdel Rahman, who heads the UK-based Syrian Observatory for Human Rights. 

Conditions were even more desperate in the coastal city of Mariupol, which has been pummelled by Russian forces in a two-week siege that has left some residents crushed in the rubble and many others dying in a winter freeze with no heat, food or clean water. Officials can no longer account for the number of dead and missing. 

Officially, 2400 civilians killed in Mariupol have been identified, but Pyotr Andryushchenko, an adviser to the city government, said he believed the toll was far higher, possibly as many as 20,000. Ukrainian estimates of the number of people trapped have ranged from 200,000 to 400,000. 

Andryushchenko said 2000 vehicles had managed to escape Mariupol and that another 2000 were packed and ready to leave. Officials told civilians to "delete all messages and photos from phones" in case Russian soldiers searched them for signs of support for Ukrainian forces. 

A firefighter walks outside a destroyed apartment building after a bombing in a residential area in Kyiv, Ukraine, on March 15. Photo / AP 

In Kherson, a southern city under Russian occupation, the mayor said members of Russia's national guard were rounding up activists who opposed Russia's presence, possibly trying to recruit them through coercion. 

"They're all in the city, in the jail," Mayor Igor Kolykhaev wrote in several text messages, referring to the activists. Russian troops, he said, "collect them, hold them, work them over and release them". 

Kherson was the first major city to fall to Russian forces. Although Kremlin officials had predicted that the Ukrainian people would welcome their "liberation" by Russian troops, residents of Kherson have been defiant, regularly gathering in the central square to protest against the Russian presence, even when Russian troops fire into the air to disperse them. 

Russia claimed to have captured the entire Kherson region, potentially strengthening its ability to push west toward the strategic port cities of Mykolaiv and Odesa. 

A senior Ukrainian military official, speaking on the condition of anonymity, confirmed that Russian forces were in control of much of the Kherson region but said Ukrainian forces were attacking their positions and inflicting losses. 

Negotiations via video link between Russia and Ukraine continued for a second day yesterday, although Putin doused prospects of any imminent breakthrough. 

In a phone call with the president of the European Council, Charles Michel, Putin complained that "Kyiv is not demonstrating a serious attitude toward finding mutually acceptable solutions", according to the Kremlin. 

A top Ukrainian negotiator, presidential adviser Mykhailo Podolyak, described the latest round of talks with the Russians, held via video conference, as "very difficult" and said there were "fundamental contradictions" between the two sides, but added that "there is certainly room for compromise". He said the talks will continue. 

Another aide to Zelenskyy, Ihor Zhovkva, struck a more optimistic note, saying the negotiations had become "more constructive" and that Russia is no longer demanding that Ukraine surrender. 

Before the talks, Russian Foreign Minister Sergey Lavrov said Moscow would press Ukraine to drop its bid to join Nato, adopt a neutral status and "demilitarise". 

In a statement that seemed to signal potential grounds for agreement with Moscow, Zelenskyy told European leaders gathered in London that he realises Nato has no intention of accepting Ukraine. 

"We have heard for many years about the open doors, but we also heard that we can't enter those doors," he said. 

Nato does not admit nations with unsettled territorial conflicts. 

Zelenskyy has said in recent weeks that Ukraine could consider a neutral status for his country but needs strong security guarantees from both the West and Russia. 

- Agencies