As he faces scathing criticism over the Taliban's lightning conquest of the war-torn country, President Joe Biden has stated that he stands "squarely" behind the US withdrawal from Afghanistan.
"How many more American lives are we willing to risk?" the Democratic president enquired.
"There was never a good time to withdraw US forces," he said, despite the "messy" pullout.
After Afghan President, Ashraf Ghani fled and his government collapsed, the Taliban declared victory on Sunday.
The militants' return to power brings an end to a US-led coalition's presence in the country after nearly two decades.
Kabul was the last major Afghan city to fall to a Taliban offensive that began months ago but accelerated in recent days as they gained territory, shocking many observers.
Mr. Biden's speech came after a dramatic day at Kabul's international airport on Monday, when hundreds of civilians fleeing the country forced their way in.
Many people flocked to the runway to run alongside a moving military transporter plane as it prepared to take off.
Some clung to the plane's side, and at least two of them are said to have died after falling from the plane after it had taken off.
Two armed Afghans who were part of the crowd that breached the airport perimeter were killed by American troops. A total of seven people are said to have died.
The United States temporarily halted its evacuation of Kabul, but it has now resumed.
A stunning photo taken on Sunday appears to show 640 Afghans crammed onto a US military cargo plane bound for Qatar.
According to the website, panicked civilians scrambled up the loading ramp, but the crew decided it was best to take off rather than force the Afghans off.
Separately, the Taliban has announced a general amnesty for government officials, urging them to return to work.
Officials should "continue their duties without fear," according to a statement.
'The correct choice'
Mr. Biden returned to the White House on Monday from the presidential retreat at Camp David to make his first public comments on Afghanistan in nearly a week.
"If anything, the events of the last week confirm that ending US military involvement in Afghanistan now was the right decision," said Vice President Joe Biden.
"American troops cannot and should not die in a war that Afghan forces are unwilling to fight for themselves."
Mr. Biden is facing a political backlash in Kabul as a result of his April decision to order all American troops out by September 11th, the 20th anniversary of the terrorist attacks that sparked the US invasion.
Senate Minority Leader Mitch McConnell (R-Kentucky) tweeted: "In Afghanistan, we are witnessing an unmitigated disaster. The US's reputation will be tarnished as a result of the Biden Administration's retreat."
Former US President George W. Bush, who authorized the military intervention in 2001, said he was "watching with deep sadness the tragic events unfolding in Afghanistan."
"The Afghans who are now in the greatest danger are the same ones who have been at the forefront of progress within their own country," Mr. Bush said, adding that the US has "the legal authority to cut red tape for refugees during urgent humanitarian crises."
Mr. Biden stated in his speech that the US mission in Afghanistan was never intended to be about nation-building.
He claimed that as Vice President, he opposed former President Barack Obama's 2009 deployment of thousands of more troops into the country.
Mr. Biden also mentioned that he inherited a deal with the Taliban negotiated by former President Donald Trump, which calls for the US to leave Afghanistan by May of this year.