U.S. intelligence agencies have told the Biden administration that the Taliban could overrun most of Afghanistan within two to three years if U.S. troops leave before a power-sharing deal is reached between the warring sides, a news report said on Friday.

Such a takeover potentially would allow al-Qaeda to rebuild in Afghanistan, the New York Times reported, quoting anonymous U.S. officials.

This comes as President Joe Biden continues to review the agreement signed between the US and Taliban in February last year that includes a May 1 troop withdrawal.

According to the Times report, some U.S. officials who favor keeping American troops in Afghanistan are using the intelligence report to argue that the soldiers should remain beyond the deadline.

The classified intelligence assessment was prepared last year for the Trump administration, the Times reported.

On Thursday Biden told his first White House news conference that it would be hard to comply with the deadline, which also requires the departure of about 7,000 NATO forces.

However, Biden said he “could not picture” U.S. troops being in the country next year.

The Taliban on Friday said it would resume hostilities against foreign forces – which ended under the U.S.-Taliban deal – if they remain beyond the deadline.