The 11-member Trans-Pacific Partnership trade bloc has agreed to open accession talks with the UK.
The British government, which asked to join the TPP in February, said membership was a huge opportunity in a post-Brexit world.
A working group is now expected to be set up to discuss tariffs and rules governing trade and investment.
The UK is not expected to join the TPP, which includes Australia, Mexico and Japan, until next year at the earliest.
International trade secretary Liz Truss said in a statement the decision to begin the accession process was "excellent news".
"It will help shift our economic centre of gravity away from Europe towards faster-growing parts of the world, and deepen our access to massive consumer markets in the Asia Pacific.
"We would get all the benefits of joining a high-standards free-trade area, but without having to cede control of our borders, money or laws." ?
She said the government would present plans to Parliament "in the coming weeks" before starting negotiations.
Since Brexit, the government has sought to replace many of the trade deals it had as a member of the EU, but has yet to sign one with a new country or trade area.
China, South Korea, Taiwan and Thailand have also expressed interest in joining the TPP, which covers a market of nearly 500 million people.
The US was initially involved in the process to set up the bloc, but pulled out on former President Donald Trump's first day in office in 2017.
The TPP's current members are Japan, Malaysia, Vietnam, Singapore, Brunei, Australia, New Zealand, Canada, Mexico, Chile and Peru.
The UK is currently negotiating a trade deal with Australia, which has raised fears among British farmers that their domestic markets could be flooded with cheaper beef and lamb. Critics have said an Australia deal will be used as a template for a TPP agreement.
However, the UK government has said farmers and exporters generally should view such deals as opening up new markets overseas.