US forces will stay in Afghanistan until all US citizens are out of the country, even if that means staying beyond the August 31 deadline, President Joe Biden told ABC News in an interview on Wednesday.

The president said he was committed to getting all Americans who want to leave Afghanistan out of the country. His administration had set the end of August as the deadline for all troops to leave.

But he accepted the possible need to stay longer. "If there are American citizens left, we're going to stay until we get them all out," he said.

Will the US evacuate all local helpers?

Biden also reiterated his pledge to help evacuate those Afghans, and their families, who had helped the US army during their 20-year stay in the country.

He said that there were "somewhere between 50 and 65,000" eligible Afghans. However, his remarks regarding whether US security forces would stay longer to help evacuate locals were less clear.

"The commitment holds to get everyone out that in fact we can get out and everyone that should come out," the president said.

"Americans should understand that we're going to try to get it done before August 31," he added.

Chaos was inevitable

US forces have been making attempts to evacuate people from Kabul airport since the Taliban's surprise takeover of power on Sunday.

The Islamist militants' rapid victory in the Afghan capital led to scenes of chaos at the airport as people scrambled to get out of the country and flee persecution.

US troops have since regained control over the airport vicinity and have been flying people out with military transport aircraft.

Biden and other NATO leaders have faced criticism over the bungled handling of the military withdrawal that left the way open for the Taliban's return to power, leaving many of their former local helpers in danger.

But the US president rejected the idea that things could have been handled better. "The idea that somehow there was a way to have gotten out without chaos ensuing, I don't know how that would happen," he said.

Questions remain over whether it will be possible to evacuate people who are outside of the Afghan capital.