US President Joe Biden and Chinese leader Xi Jinping stressed their responsibility to the world to avoid conflict as the heads of the two top global economies gathered for hours of talks on Monday.

"It seems to me our responsibility as leaders of China and the United States is to ensure that our competition between our countries does not veer into conflict, whether intended or unintended," Biden said.

"Just simple, straightforward competition."

The United States and China disagree on the origins of the Covid-19 pandemic, trade and competition rules, Beijing's expanding nuclear arsenal...