President Joe Biden and his Chinese counterpart, Xi Jinping, closed the book on their diplomatic relationship Saturday, meeting for a final time amid uncertainty over what the next Donald Trump presidency might portend for their two countries’ ties.

Donald Trump has made a tougher stance toward China central to his pitch on foreign policy, even as Joe Biden and Xi Jinping sought to lower tensions before the next president takes office.

We are the most important alliance – or the most important relationship in the entire world, and how we’re getting along together can impact the rest of the world,” Biden said.