U.S. President Joe Biden suggested the possibility of an in-person meeting with Xi Jinping during a phone call last week, but the Chinese president declined as he continues to avoid leaving his country even for major gatherings amid the COVID-19 pandemic.

Biden suggested the two leaders meet at some point in the next few months, according to people familiar with the conversation who were granted anonymity to discuss it.

Xi hasn’t left China for more than 600 days, the longest stint of any Group of 20 leader. Instead, he’s made virtual appearances at events including a summit of leaders from the BRICS nations. He isn’t expected to appear at next week’s United Nations General Assembly in New York either, though Chinese presidents seldom attend those gatherings.