US President Joe Biden and Chinese President Xi Jinping shook hands Wednesday and pledged to reduce tensions as they met for the first time in a year at a high-stakes summit in California.

A smiling Biden greeted Xi after the Chinese leader stepped out of a black limousine at the scenic Filoli country estate in the California foothills near San Francisco, before the two leaders shook hands on the front steps.

The two leaders then headed inside for painstakingly choreographed, closed-door talks on issues including Taiwan, sanctions and trade that have roiled relations between the world's largest economies.

Biden opened his remarks by saying that tensions should "not veer into conflict."

Xi responded by saying that "turning their back on each other is not an option" for the superpowers.

Biden was to give a solo press conference at 4:15 pm (0015 GMT Thursday) to discuss the summit, which was being held on the sidelines of the APEC summit in San Francisco, the White House said.

Protesters lined part of the route of Biden's motorcade from San Francisco, many with pro-Xi signs and red and yellow Chinese flags hung up on security fences.

US officials have played down the chance of major breakthroughs although an agreement on restoring a hotline between the Chinese and US militaries on the cards, along with cooperation on stopping supplies of the drug fentanyl.

But the main goal of the talks -- which are taking place at the setting for the famed 1980s US soap opera "Dynasty" -- is to restore predictability to the relationship, US officials say.

The last time Biden and Xi met in person was in Bali in November 2022, and relations nosedived after the United States shot down an alleged Chinese spy balloon in February this year.

The talks, which come after months of delicate diplomatic negotiations, come against the backdrop of a long struggle for global primacy between the United States and an increasingly assertive China.

One of the most sensitive issues is Taiwan, the self-ruling democracy over which Beijing claims sovereignty and which it has not ruled out seizing by force.

Biden was expected to tell Xi that the United States will stick to its "One China" policy that emphasizes it does not support Taiwanese independence, but that it will continue to give Taiwan military aid.

"We do not want to see the tensions across the Taiwan Strait evolve into any kind of conflict", White House National Security Council spokesman John Kirby told reporters hours before the meeting.

Biden was also expected to "raise concerns over human rights in China" including the repression of the Uyghur Muslim minority, added Kirby.

The 80-year-old Biden held out an olive branch to Xi, 70, on the eve of the talks, insisting that the United States was "not trying to decouple from China" and wanted to improve the relationship.

But Biden could not resist adding at a fundraising dinner that under communist leader Xi China faced "real problems," while Biden claimed to be "reestablishing American leadership in the world."

China responded with a foreign ministry spokeswoman pointing out all countries had problems, including the United States, while sticking to positive talking points on the summit.

- 'Important for everyone' -

Expectations of major announcements are low but the two countries have trailed a series of possible wins from Xi's first visit to US soil since he was hosted by then-president Donald Trump in 2017.

One is the restoration of the two countries' military hotline, which Beijing severed after then-House speaker Nancy Pelosi visited Taiwan in 2022. 

There were also hopes of "progress" on cooperation to limit Chinese exports of ingredients for fentanyl, the opioid drug sweeping America.

The two leaders were additionally expected to discuss the Israel-Hamas conflict and the Ukraine war.

On the eve of the summit, China and the United States also pledged to work more closely together on global warming.

Russia, a partner of China in what Washington sees as a growing authoritarian alliance, welcomed the San Francisco meeting, with the Kremlin calling the talks "important for everyone."

For his part Xi was expected to push for an end to trade curbs and sanctions, with the Chinese economy struggling to shore up growth after its tough zero-Covid policy. 

The Chinese leader was to host a dinner with US executives after the summit.