President Joe Biden spent more than four hours in a meeting with China's President Xi Jinping in the Bay Area on Wednesday as part of the Asia-Pacific Economic Cooperation summit that has been taking place in the region for the past week.

Biden and Xi met at the Filoli estate in Woodside south of San Francisco on Wednesday morning, Nov. 15, for the bilateral meeting that started with both heads of state acknowledging a tense relationship between the two world powers.

"We've known each other for a long time, we haven't always agreed, which is no surprise to anyone," Biden said. "We have to ensure competition does not veer into conflict."

A pool media report from the meeting, citing a "senior administration official," said the talks covered issues such as the Chinese role in the production of fentanyl, a drug that has fueled an opioid overdose crisis in America; reinstating talks between the two countries' militaries, collaboration on artificial intelligence issues, and ongoing conflicts between Russia and Ukraine as well as the Israel-Hamas war.

The status of Taiwan and Xi's preference for a "peaceful reunification" of the country with China was "the biggest most potentially dangerous issue in U.S.-China relations," the unnamed official said, according to the pool report.

"I think President Biden responded very clearly that the longstanding position of the United States was a determination to maintain peace and stability," the official said of the president's response. "That we believed in the status quo. And that we asked the Chinese to respect the electoral process in Taiwan."

Biden also attended an event at the Exploratorium science museum on San Francisco's waterfront later Wednesday evening with Gov. Gavin Newsom, Speaker Emerita Nancy Pelosi, U.S. Sen. Alex Padilla, Mayor London Breed and others.

Vice President Kamala Harris, who served as San Francisco's district attorney before her rise to state and federal office, spoke before Biden at the Exploratorium event, which also featured a video by Golden State Warriors star Stephen Curry and coach Steve Kerr, along with women's sports stars Brandi Chastain and Kristi Yamaguchi.

Biden then spoke to a pool reporter after a fireworks show that followed the event and a concert by singer Gwen Stefani.

"We owe a big debt of gratitude to the new mayor of the city of San Francisco," Biden said in an apparent reference to Breed, who has been mayor since 2018. "And Gov. Newsom, he's doing a hell of a job."