​The chairman of the Joint Chiefs of Staff told senators on Sunday that he will move up the assessment of how soon terror groups like al-Qaeda could reform in Afghanistan in the wake of the Taliban’s swift takeover of the war-torn nation, according to a report.

During a ​briefing for a bipartisan group of lawmakers, Gen. Mark Milley was asked by Sen. Lindsey Graham (R-SC) if he and Defense Secretary Lloyd Austin would revise an assessment to Congress in June that there is a “medium” risk of terrorist organizations reconstituting in Afghanistan in less than two years.

​”Yes,” Milley replied, adding that he would be happy to brief the senators further in a classified setting, Axios reported, citing three sources on the phone call.

The US and its allies launched the war in Afghanistan in October 2001 because the Taliban provided al-Qaeda support and safe harbor while the terror group planned the 9/11 attacks.

The briefing by Milley, Austin and Secretary of State Antony Blinken came amid rapid developments in Afghanistan.

The US military used helicopters to ferry diplomats and staffers from the US Embassy in Kabul after the Taliban entered the capital city on Sunday, catching the Biden administration flat-footed with their dizzying advance.

Shortly after the insurgent group entered the city, Afghan President Ashraf Ghani fled the country.

As the trio of administration officials briefed them, many of the senators were getting real-time updates of the deteriorating situation on their cell phones, the report said.

In a briefing for House members, Republican leader Kevin McCarthy compared the US’s evacuation of the embassy in Kabul to Saigon in 1975 and blasted Ghani for running.

Taliban fighters pose for a photograph while raising their at the Ghazni provincial governor's house.