House Minority Leader Kevin McCarthy and Senate Minority Leader Mitch McConnell and are demanding a classified briefing from the Biden administration on the government's plan to ensure safe passage for U.S. citizens out of Afghanistan.

Why it matters: By demanding an official briefing for the so-called "Gang of Eight" on the immediate challenges facing the Biden administration, the top two congressional Republicans are indicating that they plan press the White House on a range of issues.

• “It is of the utmost importance that the U.S. Government account for all U.S. citizens in Afghanistan and provide the necessary information and means of departure to all those Americans who desire to leave the country," they wrote to Biden on Wednesday.
• Among other issues, they want to know how many U.S. citizens remain in Afghanistan and how the government plans to evacuate anyone outside of Kabul who cannot reach the airport.

Driving the news: In an interview with ABC News, Biden defended his decision to withdraw, but hinted that he would launch his own review of how the country fell so quickly.

• “We're gonna go back in hindsight and look,” he said.
• “But the idea that somehow, there's a way to have gotten out without chaos ensuing, I don't know how that happens. I don't know how that happened," Biden said.

The big picture: Gen. Mark Milley, chairman of the Joint Chiefs of Staff, said Wednesday that the U.S. military's intelligence did not indicate that Afghanistan would fall as quickly as it did to the Taliban.

• Milley's comments come as intelligence communities have pushed back on claims that the Afghan collapse was a surprise. Several leaks have asserted that the intelligence agencies provided substantial information regarding Afghanistan's potential fall.
• "The time frame of a potential collapse was widely estimated, it ranged from weeks to months, even years following our departure," Milley said in a press briefing.

Go deeper: McConnell’s and McCarthy’s call comes after Senate Intelligence Committee Chair Mark Warner (D-Va.) indicated Monday that he plans to work with other congressional committees to investigate any potential intelligence failures.

• Warner said in a statement Monday that he would “ask tough but necessary questions about why we weren’t better prepared for a worst-case scenario involving such a swift and total collapse of the Afghan government and security forces."