UK Prime Minister Rishi Sunak is to fly to California later to discuss key details of a new defence agreement with his Australian and US counterparts.
The 2021 Aukus pact aims to counter what the three nations see as China's threat in the Indo-Pacific region.
At the time, China condemned the agreement as "extremely irresponsible".
The meeting with US President Joe Biden
and Australian PM Anthony Albanese is set to agree the supply of nuclear-powered submarines to Australia.
Speaking ahead of the talks in San Diego, Mr Sunak said the UK's global alliances were "our greatest source of strength and security".
During the trip - Mr Sunak's first to the US as PM - he is also set to unveil the UK's new integrated review of defence and foreign policy, which have been updated after Russia's invasion of Ukraine.
Mr Sunak said the review will reflect "the future we want to deliver" to the UK - "secure, prosperous and standing shoulder to shoulder with our partners".
The plans to finalise the key details of the Aukus (Australia-UK-US) pact come in light of strained diplomatic relations between the West and China.
Downing Street has recently cited "increasingly concerning behaviour of the Chinese Communist Party" and just last month the former head of MI6 said the UK must "wake up" to the threat posed by China's challenges to global security.
Meanwhile, the US and China continue to clash on issues including Taiwan, China's militarisation of the South China Sea and the origins of Covid
-19. And more recently, the spy balloon saga heightened tensions between the superpowers.
Beijing has acknowledged that China-US relations have "seriously deviated". Chinese Foreign Minister Qin Gang said the diplomatic crisis caused by the balloon incident could have been averted but the US acted with "the presumption of guilt".
The deal is set to see Australia become just the seventh nation in the world to operate nuclear-powered submarines, after the US, UK, France, China, India and Russia.
The plan is for nuclear submarines to be built in Adelaide, south Australia, with the UK and US providing consultation on technology for their production.
The UK is hoping the Aukus pact will result in work for UK shipyards, with reports suggesting Canberra could select to build a modified version of the British Astute-class submarine, while taking delivery of up to five US Virginia-class submarines during the production stage.
In addition to submarines, the pact is committed to information and technology exchange between the three nations in areas ranging from intelligence and quantum technology to the acquisition of cruise missiles.
But the signing of the pact sparked a row with France, which lost a deal with Australia to build 12 diesel-powered submarines.