The leaders of the United States, United Kingdom and Australia are to meet in California with US President Joe Biden expected to announce a new nuclear submarine deal with Canberra that aims to counter China in the Pacific.

The meeting in San Diego on Monday comes 18 months after the creation of a new US-UK-Australia security pact, known as AUKUS, that has enabled Australia to access nuclear-powered submarine technology.

The pact – which also covers cooperation on artificial intelligence, hypersonic weapons and other advanced technologies – is part of an ongoing effort by the three nations to respond to Chinese military might.

China represents “a systemic challenge for the world order”, British Prime Minister Rishi Sunak said in an interview with NBC News on Sunday from California, where he met with his Australian counterpart, Anthony Albanese, a day before Biden’s arrival.

Since AUKUS was launched, Beijing has repeatedly accused the trio of adopting a “cold war mentality” that risks greater escalation.

On Monday, the US, British and Australian leaders are set to announce that Australia is buying up to five Virginia-class submarines as part of the pact, according to multiple reports in US and international media.

The sale is part of a long-term, multistage plan destined to make Australia a full partner in fielding top-secret US nuclear technology previously only shared with the UK.

After the sale of the Virginia-class submarines, which have an estimated value of $3bn each, Australia and Britain would then embark on building a new submarine model with US technology and support, according to the media reports.

Australia is aiming to deliver those new vessels to its navy in the 2040s, The New York Times reported.

The agreement will also see a force of US and British submarines deployed in Western Australia to help train Australian crews and bolster deterrence, the Reuters news agency said.

The deal, which will take years to be fully realised, marks an ambitious shift for the three allied nations as they seek to respond to Beijing’s rapidly expanding military power in the Pacific.

That has included the building of a sophisticated naval fleet and the construction of artificial islands that observers say China has turned into military bases.

Australia’s participation in AUKUS prompted a brief but heated spat with France after Canberra pulled out of an earlier deal to replace its ageing fleet of diesel-powered submarines with $66bn of non-nuclear French vessels.

Compared with the Collins-class submarines due to be retired by Australia, the Virginia-class is almost twice as long and carries nearly three times more crew at 132.

The US vessels are able to stay submerged almost indefinitely and launch powerful cruise missiles.

For its part, China has argued AUKUS risks setting off an arms race and violates the Nuclear Non-Proliferation Treaty.

Beijing has said the transfer of nuclear weapons materials from a nuclear weapons state to a non-nuclear-weapons state is a “blatant” violation of the spirit of the treaty.

“We urge the US, the UK and Australia to abandon the Cold War mentality and zero-sum games, honour international obligations in good faith and do more things that are conducive to regional peace and stability,” Chinese Ministry of Foreign Affairs spokeswoman Mao Ning told reporters in Beijing.

Australian officials have pushed back against the criticism, arguing that they are working to acquire nuclear-powered, not nuclear-armed submarines.

Prior to Monday’s meeting, the UK announced $6bn in additional military funding over the next two years to “replenish and bolster vital ammunition stocks, modernize the UK’s nuclear enterprise and fund the next phase of the AUKUS submarine programme”.

In a statement, Downing Street added that longer-term spending increases for the defence budget are being considered.

During his California visit, Biden will hold separate meetings with Albanese and Sunak before travelling to Monterey Park to discuss gun violence protection after the California city suffered a deadly shooting in January.

Biden will then travel to Nevada to discuss his plans to lower prescription drug costs.

The US president’s trip also is to include several fund-raising stops as he is expected to officially announce his 2024 presidential re-election bid next month.