Joe Biden committed to participating in three planned debates against President Trump while criticizing the president for trying to add an additional debate.

“Joe Biden looks forward to facing Donald Trump in a multi-debate series that the American people have come to expect from their leaders; we hope that President Trump would not break that tradition or make excuses for a refusal to participate,” Biden campaign manager Jen O’Malley Dillon wrote Monday in a letter to the nonpartisan Commission on Presidential Debates, the Washington Post reported.