Meanwhile, Trump has placed several calls over the past week to some family members of the 13 service members killed by an Islamic State-Khorasan terrorist attack during the withdrawal. Several have invited him to attend the funerals, and he has suggested he may try to do so.

Trump and his allies have seen the calamitous end to the war in Afghanistan as a potent political opportunity as he weighs a potential 2024 reelection bid — even though Trump himself advocated for the withdrawal, negotiated with the Taliban before leaving office and urged Biden to leave even sooner.

As Biden plans to attend several solemn ceremonies Saturday to mark the 20th anniversary of the 9/11 attacks. Trump has not announced any plans to attend memorial events, though an adviser said he may attend one in Manhattan. That evening, he is slated to provide color commentary for a pay-per-view heavyweight boxing match at the Seminole Hard Rock Hotel and Casino in Hollywood, Fla.