While overseas travel has resumed for New South Wales residents as of today, Western Australia's Government has remained firm on their hard border with the state. 

Despite NSW only recording 135 cases on Monday, WA Premier Mark McGowan has continued to classify NSW as an "extreme risk" jurisdiction, saying he fears WA residents could access overseas travel via Sydney, before returning to the state. He also expressed fears relaxed travel restrictions could bring a spike in infections, threatening the state's current zero seven-day case average. 

"It could mean that under NSW's arrangements, if we drop them to what's called 'high', people could go out of NSW overseas, come back into NSW without quarantining and then demand to come back to WA," he said. 

"This is the quandary we are in," he continued. "We don't want to encourage that because all it will mean is we get spread of the virus before such time as we have high enough levels of vaccination." 

McGowan also said WA's vaccination rates would need to reach a "very high" level before travellers would be allowed into the state from NSW, Victoria and overseas. 

This comes as NSW's 14-day virus average dropped to 277 as of Sunday. The state has also reached a 87.5 per cent full vaccination rate for people over the age of 16, with WA's double dose rate sitting at 60.6 per cent for their population aged 12 and over. 

Despite this, the western state is the only Australian jurisdiction that has yet to cement a formalised reopening timeline, with the Premier revealing no plans to re-open the state for fully-vaccinated travellers. 

Speaking to media on Friday, McGowan hinted that the highly-anticipated date could be months away, with international travel slated for "the first half of next year". 

Sydney residents can now travel out of the country, but they can't travel to WA. Photo / Getty Images 

As it stands, interstate travellers from medium (ACT), high or extreme risk jurisdictions (Victoria and NSW) are strictly banned from entering WA, regardless of their vaccination status. 

Residents from states classified as "extreme risk" are unable to enter the state even on compassionate grounds, with only government officials, military personnel, MPs and skilled specialists in time-critical services matching the strict criteria for 'approved travellers'. 

Approved travellers entering from the ACT, NSW and Victoria also need to be fully-vaccinated in order to enter the state, in addition to undertaking 14-day quarantine and testing requirements. 

In comparison, travellers from the very low-risk jurisdictions of the NT, SA, Tasmania and Queensland are allowed to freely travel into the state with no vaccination or quarantine measures.