Joe Biden has said US troops may stay past a 31 August deadline so as to evacuate all Americans from Afghanistan, and defended the withdrawal, saying there was no way for the US to pull out “without chaos ensuing”.

As critics in the US and abroad questioned his handling of the withdrawal, the president said in his first on-camera interview since the Taliban took Kabul that troops would stay in the country to get American citizens out.

“If there’s American citizens left, we’re going to stay until we get them all out,” Biden told ABC News, implying that he would listen to US lawmakers who had pressed him to extend the 31 August deadline he had set for a final pullout.

Asked if he thought the handling of the crisis could have gone better, Biden said: “No.”

“We’re gonna go back in hindsight and look … but the idea that somehow, there’s a way to have gotten out without chaos ensuing, I don’t know how that happens,” he told ABC’s George Stephanopoulos.

The sentiment contradicts what Biden had said weeks back, when he insisted that the “likelihood there’s going to be the Taliban overrunning everything and owning the whole country is highly unlikely”.

The speed with which Taliban forces retook Afghanistan, as US and other foreign forces withdrew, has led to continued chaotic scenes at the airport with diplomats, foreign citizens and Afghans trying to flee. They are being impeded by crowds and Taliban checkpoints, with reports of citizens being crushed and beaten by Taliban force who now control the outside of the airport.

The US said it has evacuated nearly 6,000 people from Afghanistan since Saturday but thousands of Americans and tens of thousands of Afghans who want to leave the country remain and it is feared the slow speed of evacuations was putting lives at risk. Educated young women, former US military translators and other Afghans most at-risk from the Taliban appealed to the Biden administration to get them on evacuation flights as the United States as quickly as possible.

“If we don’t sort this out, we’ll literally be condemning people to death,” said Marina Kielpinski LeGree, the American head of nonprofit organisation Ascend.

Though the Taliban has appealed for international aid to continue to flow into the country, which currently accounts for 42.9% of GDP, the International Monetary Fund joined growing number of donors and lenders who said they would suspend funds going to Afghanistan. IMF Resources of over GBP268m had been set to arrive this month but an IMF spokesperson said “lack of clarity within the international community” over recognising a government in Afghanistan meant they would no longer send the funds.

It has also emerged that classified intelligence documents from the past few weeks gave multiple warnings to the Biden administration of the prospect of an imminent Taliban takeover of Afghanistan and the likely rapid collapse of Afghan troops, with Kabul portrayed as highly vulnerable. It raises questions as to why the US administration was not better prepared for security and evacuations in the event the Taliban took control.

Biden told ABC the Taliban were cooperating in helping get Americans out of the country, but admitted “we’re having some more difficulty” in evacuating US-aligned Afghan citizens.

He said: “They’re cooperating, letting American citizens get out, American personnel get out, embassies get out, et cetera, but they’re having … we’re having some more difficulty having those who helped us when we were in there.”

Biden appeared dismissive of images that emerged on Monday of packed US military planes taking off from Kabul airport as people clung to their sides. At least two people apparently fell to their deaths from the undercarriage soon after takeoff.

Stephanopoulos said: “We’ve all seen the pictures. We’ve seen those hundreds of people packed in a C-17. We’ve seen Afghans falling … “

Biden interrupted and said: “That was four days ago, five days ago!”

The president was asked what he thought when he first saw those pictures. Biden replied: “What I thought was: we have to gain control of this. We have to move this more quickly. We have to move in a way in which we can take control of that airport. And we did.”

Former Afghan president Ashram Ghani, who fled the country of Sunday as Taliban troops entered Kabul, made his first appearance since it emerged he had been granted entry into the United Arab Emirates on “humanitarian grounds”.

Ghani, speaking in a video posted on Facebook, said he supported talks between the Taliban and former government officials, led by former president Hamid Karzai. He said he was “in talks” to return to Afghanistan and that he was making efforts to “safeguard the rule of Afghans over our country”.

Looking pale and gaunt, Ghani denied he had betrayed Afghans by fleeing and said the Taliban had entered Kabul, despite an agreement they would not.

“Do not believe whoever tells you that your president sold you out and fled for his own advantage and to save his own life,” said Ghani. “These accusations are baseless.”

He also denied reports he had taken money with him when he fled. “I was expelled from Afghanistan in such a way that I didn’t even get the chance to take my slippers off my feet and pull on my boots,” said Ghani.