The full withdrawal will happen before or by the 20th anniversary of the Sept. 11, 2001, attacks, which catapulted the United States into the longest war in its history. It extends the May 2021 deadline set by the Trump administration.
The Taliban had threatened an increase in violence should the United States keep armed forces in the country beyond May 1. Sources told the Post the administration hoped that by setting a new, specific date, it could avoid that violence.
A senior administration official told CNN that U.S. officials told the Taliban that any attack on U.S. troops in the meantime would be met with retaliation.
There are currently more than 2,500 U.S. troops in Afghanistan.
Sen. Lindsey Graham, R-S.C., a supporter of a U.S. military presence in Afghanistan, called the move "irresponsible."
"A full withdrawal from Afghanistan is dumber than dirt and devilishly dangerous," he said. "President Biden will have, in essence, canceled an insurance policy against another 9/11.
"A residual counterterrorism force would be an insurance policy against the rise of radical Islam in Afghanistan that could pave the way for another attack against our homeland or our allies."
Defense Secretary Lloyd Austin made a surprise visit to Afghanistan on March 21, but at the time declined to say whether the Taliban had met the necessary conditions under a 2020 peace agreement to qualify for full withdrawal of U.S. forces. He said he didn't bring up the issue with Afghan President Ashraf Ghani.
"What I will say is that it is obvious the level of violence remains pretty high in the country," he said. "We'd really like to see that violence come down. If it does not come down it can begin to set the condition for some really fruitful diplomatic work."