UPDATED 12.51PM: A secretive and controversial free trade deal between Pacific Rim nations has finally been signed.

Trade ministers and their negotiators have come to what they're calling a "broad agreement" over the Trans-Pacific Partnership, an immense deal encompassing 40 percent of the global economy which could making sweeping regulatory changes to many of the nations involved.

MORE: TPP Negotiations: Timeline & stumbling blocks

Rachel Smalley: TPP not perfect, but still a win

LISTEN TO MIKE HOSKING'S FULL INTERVIEW WITH TIM GROSER ABOVE

Mike's Minute: Free trade is good trade

It comes after five years of talks and an ultimate push of six days in Atlanta, which were delayed by negotiations over how long pharmaceutical corporations should be allowed to have a monopoly period on next-generation drugs.

Ten things trade reps say the TPP will do, according to their official statement. pic.twitter.com/2fGWALIs78

— Michael Sergel (@michaelsergel) October 5, 2015

United States Trade Representative Michael Froman officially announced the hard-won deal in the early hours of this morning.

The Trans Pacific Partnership would deliver New Zealand its long sought-after free-trade deal with the United States, the largest economy in the world, and Japan, the third largest economy. Trade Minister Tim Groser said during a press conference that in the long run the agreement eliminates tariffs on around 93 percent of New Zealand exports to the US, Canada, Japan, Mexico, and Peru.

Prime Minister John Key welcomed the deal, saying the estimated benefit is expected to be at least $2.7 billion a year by 2030.

Tim Groser says New Zealand fought hard to remove dairy barriers, but the TPP is about the "bigger picture". pic.twitter.com/vvZFUBioi1

— Michael Sergel (@michaelsergel) October 5, 2015

However, the dairy industry are disappointed by the lack of gains in their sector.

According to Tim Groser, some dairy products will get tariff elimination but others have proven to be too difficult .

Fonterra chairman John Wilson stated that the deal was far from perfect, but farmers appreciate the few steps forward in dairy market access that the Trade Minister did manage to secure.

The Dairy Companies Association of New Zealand has voiced their disappointment that the TPP hasn't delivered a bigger opening. Chairman Malcolm Bailey said that while a further market opening will be needed to help address price volatility in the global dairy market, the deal does contain some useful improvements, like eliminating some trade barriers.

"[The United States is] growing their dairy industry and they're growing their exports so we thought was in their interest to push for a much more liberal deal on dairy, but it wasn't to be."

"We did try very hard," Bailey said.

11 men and 1 woman fronted this morning's official TPP announcement. pic.twitter.com/qPWJYErU5i

— Michael Sergel (@michaelsergel) October 5, 2015

Saunders Unsworth trade consultant Charles Finny pointed out the deal could be good for a number of protein products, like milk powders for children.

"Infant milk powder seemed to be liberalised into most of the markets but there will still be some quota arrangements for some products into Japan, the United States, Mexico, and Canada," Finny said.

However, Groser countered the lack of advantages for the dairy sector by saying there had some hugely positive results in areas like wine trade with the United States, and apples with Mexico.

"It's basically free trade for everything other than dairy, and on dairy it's a mixed bag."

He also said the agreement - which he refers to as "the TPP bus" - has established a direction that can be built on future trade ministers.

"If you think you shouldn't do anything because you cannot attain perfection, just remember the old phrase 'The excellent is almost always the enemy of the good'," Groser said.

"In future years we can be absolutely certain that the depths of achievement we've been able to reach at this point in our collective history will be deepened and broadened."

The Labour Party, however, believes New Zealand has missed the bus.

Acting Labour leader Annette King criticised the lack of meaningful gains for dairy, and new costs for Pharmac.

King claims the government must come clean on what "ugly compromises" it may have made behind closed doors.

"The devil is definitely in the detail in these agreements."

"New Zealanders must be told whether the government has traded away our right to further restrict foreign ownership of housing or farm land and what agreements have been made to allow foreign corporations to sue New Zealand for regulating in the public interest."

Labour's finance spokesman, Grant Robertson, is critical of a lack of gains for the dairy sector - saying the deal's failed on that score.

He's also demanding clarity as to if the TPP deal will allow the Government to restrict land sales to foreigners.

US President Barack Obama, who made the TPP a priority of his second term, said the accord reached in Georgia "reflects America's values and gives our workers the fair shot at success they deserve."

"When more than 95 per cent of our potential customers live outside our borders, we can't let countries like China write the rules of the global economy," Obama said in a statement. "We should write those rules, opening new markets to American products while setting high standards for protecting workers and preserving our environment."

More than 18,000 taxes imposed by various countries on US products will be eliminated thanks to the partnership, he added.

The US had sought 12 years of protection to encourage pharmaceutical companies to invest in expensive biological treatments, but New Zealand, Australia, and public health groups had sought a period of five years to bring down drug costs and the burden on state-subsidized medical programs - like Pharmac.

A compromise was reached but the agreed protection period has not been confirmed.

A complete text of the TPP will now be prepared for public release including a legal review, translation, drafting, and verification. It must be released within 30 days.

Under a rule set by the United States, any agreement cannot be signed until 90 days after negotiations end, to allow time for full consideration of its pros and cons.

In New Zealand, the Ministry of Foreign Affairs will provide a report to the Cabinet on the costs and benefits.

The Cabinet will then decide whether to approve the agreement.

Once the Cabinet approves the deal, the full text will be tabled in Parliament. It will then be scrutinised by a parliamentary committee, which will hear submissions from the public.