U.S. Secretary of State Antony Blinken beat back criticism of the withdrawal of U.S. troops from Afghanistan on Monday at a contentious congressional hearing where at least two Republicans called on him to resign.

In five hours of often testy exchanges with lawmakers, Blinken defended President Joe Biden's decision to pull out and pushed back on accusations that the State Department should have done more to help Americans and at-risk Afghans to be evacuated, blaming the previous administration for lacking a plan. He repeatedly noted that Republican former President Donald Trump had negotiated the withdrawal agreement with the Taliban, and said Biden's administration could not renegotiate because of threats from the group to resume killing Americans.

"There's no evidence that staying longer would have made the Afghan security forces or the Afghan government any more resilient or self-sustaining," Blinken said. "We inherited a deadline. We did not inherit a plan," Blinken said, referring to the Trump administration's agreement to remove all U.S. forces from Afghanistan by May 1.

Members of Congress

Biden's Democrats as well as opposition Republicans – have pledged to investigate since the Taliban seized control of Afghanistan last month after a rapid advance. Blinken appeared on Monday before the House of Representatives Foreign Affairs Committee and was to testify on Tuesday before the Senate Foreign Relations Committee, the first Biden administration official to testify publicly to lawmakers since the militant group's takeover.

Fireworks had been expected, given the amount of finger-pointing over how the two-decade-long war ended. Many Republicans, particularly those closely allied to Trump, interrupted or even shouted over Blinken during the House hearing, a departure for a committee known for bipartisan cooperation. Others offered harsh criticism.

"The American people don't like to lose, especially not to the terrorists. But this is exactly what has happened," said Representative Michael McCaul, the panel's top Republican. McCaul asked why assets like the Bagram Air Base were not maintained and why the administration had not reached counterterrorism agreements with neighboring countries.

"This is a national security threat as China moves in. For all I know they make take over Bagram," McCaul said. Blinken said the United States was actively working to identify threats.

Many Questions

Lawmakers asked a long list of questions about the rapid collapse of the U.S.-backed Afghan government and scramble to evacuate 124,000 people. Democrats expressed concern about Americans and at-risk Afghans who still wish to leave, but backed the withdrawal as necessary, if painful.

"I would welcome hearing what exactly a smooth withdrawal from a messy chaotic 20-year war looks like," said Representative Gregory Meeks, the committee's chairman. Blinken praised the evacuation as "a heroic effort." He pledged that the United States will continue to support humanitarian aid to Afghanistan, but through non-governmental organizations and U.N. agencies, not the Taliban.

Afghanistan is at risk of running out of food as it faces a terrible drought in addition to political upheaval. "We need to do everything we can to make sure the people of Afghanistan don't suffer any more than is already the case," Blinken said. He said he had not spoken personally to members of the Taliban leadership.

"Any legitimacy that they may seek from the international community ... is going to be contingent on their actions," he said. Blinken said he would name a senior State Department official to focus on support for Afghan women, girls and minorities. Republicans grilled Blinken about what happened at Kabul Hamid Karzai International Airport, during the evacuation ahead of the administration's Aug. 31 deadline to leave.

Thirteen U.S. troops and dozens of Afghans were killed in a suicide bombing amid the chaos. Democrats said they wanted to address not just the seven months Biden was president before Kabul fell but all 20 years of U.S. involvement in the country – under presidents from both parties.

A U.S.-led invasion toppled the Taliban in 2001 after the Sept. 11 attacks masterminded by al-Qaida leaders based in Afghanistan.