Both men arrived Saturday morning for the second and final day of an Asia-Pacific economic summit in Peru overshadowed by the prospect of fresh trade wars and diplomatic upheaval when Trump starts his second term.

Trump’s comeback has cast a cloud of uncertainty over efforts – launched at a historic meeting between Xi and Biden in California a year ago – to ease a tense relationship between Washington and Beijing.

The White House said Saturday’s Xi-Biden meeting on the sidelines of the Asia-Pacific Economic Cooperation (APEC) summit would focus on a “delicate period of transition” and ensuring that competition with China “doesn’t veer into conflict.”

Trump’s crushing election win over Democrat Kamala Harris sent shock waves around the globe and dominated the meeting of heads of state of the 21-member APEC group.

Before their face-to-face meeting scheduled for 4:00 pm (2100 GMT), Biden and Xi were to take part in a closed-door “retreat” with other leaders from countries including Canada, Chile, Singapore, Australia, Malaysia and Japan.

‘Significant political change’

Xi and Biden, who will be meeting for the third time overall, warned separately at the summit on Friday of choppy waters ahead.

The Chinese president raised concerns about “spreading unilateralism and protectionism” in a written speech to the forum, China’s state news agency Xinhua reported.

For his part, Biden said the world had “reached a moment of significant political change.”

Billionaire Republican Trump has signalled a confrontational approach to Beijing, threatening to impose tariffs of up to 60 per cent on imports of Chinese goods to even out what he says is a trade imbalance.

He has also named two major China hawks in his top team, including Marco Rubio for secretary of state.

As Biden raced to salvage what he can of his foreign policy legacy, he met Friday with the leaders of Japan and South Korea – key US allies in Asia.

Biden said strong US ties with the two countries were essential for “countering North Korea’s dangerous and destabilizing cooperation with Russia” as Pyongyang sends troops to fight in Ukraine.

Alliances at risk

The return of Trump’s “America First” policies threatens alliances Biden has built on issues ranging from the wars in Ukraine and the Middle East to climate change and trade.

During his first term, Trump repeatedly threatened to cut US defence commitments to Asian and European allies if they did not carry a larger share of the financial burden for their protection.

Economists say Trump’s threat of punitive tariffs would harm not only China’s economy but also that of the United States and its trading partners.

It could also threaten geopolitical stability.

China is building up its military capacity while ramping up pressure on self-governed Taiwan, which it claims as part of its territory.

Sullivan said Xi and Biden were set to discuss Taiwan and tensions in the South China Sea, where Beijing claims large swathes of maritime territory, he said.

They would also focus on keeping communication channels open, particularly military-to-military hotlines restored last year.

Japanese Prime Minister Shigeru Ishiba expressed “serious concerns over the Chinese military’s growing activity” at a meeting with Xi at the APEC summit, the foreign ministry in Tokyo said.

The APEC summit will wrap up Saturday with Trump’s shadow still casting a pall over the international diplomatic agenda at a G20 summit in Rio de Janeiro next week.

Biden will be heading there as part of a swing through Latin America in what is likely to be his last major foreign tour.

He will stop in the Amazonian rainforest Sunday to highlight the impact of climate change – another key policy area likely to be affected by Trump, who has promised to “drill, baby, drill” for fossil fuels.