The United States struggled yesterday to pick up the pace of American and Afghan evacuations at Kabul airport.

Efforts were constrained by obstacles ranging from armed Taliban checkpoints to paperwork problems and with an August 31 deadline looming, tens of thousands remained to be airlifted from the chaotic country.

Taliban fighters and their checkpoints ringed the airport — major barriers for Afghans who fear past work with Westerners makes them prime targets for retribution.

Hundreds of Afghans who lacked any papers or promises of flights also congregated at the airport, adding to the chaos. It didn’t help that many of the Taliban fighters could not read the documents.

In one hopeful sign, State Department spokesman Ned Price said in Washington that 6,000 people were cleared for evacuation yesterday and were expected to board military flights in coming hours.

That would mark a major increase from recent days. About 2,000 passengers were flown out on each of the past two days, Pentagon spokesman John Kirby said.

Mr Kirby said the military has aircraft available to evacuate 5,000 to 9,000 people per day, but until yesterday far fewer designated evacuees had been able to reach, and then enter, the airport.

Mr Kirby said the limiting factor has been available evacuees, not aircraft. He said efforts were underway to speed processing, including adding State Department consular officers to verify paperwork of Americans and Afghans who managed to get to the airport.  

And yet, at the current rate it would be difficult for the US to evacuate  all of the Americans and Afghans who are qualified for and seeking evacuation by August 31.

President Joe Biden said on Wednesday he would ensure no American was left behind, even if that meant staying beyond August. It was not clear if Mr Biden might extend the deadline for evacuees who aren’t American citizens.

At the airport, military evacuation flights continued, but access remained difficult for many.

Yesterday, Taliban militants fired into the air to try to control the crowds gathered at the airport’s blast walls. Men, women and children fled. Navy fighter jets flew overhead, a reminder to the Taliban that the US has firepower to respond to a combat crisis.

There is no accurate figure of the number of people – Americans, Afghans or others – who are in need of evacuation as the process is almost entirely self-selecting.  

Compounding the uncertainty, the US government has no way to track how many registered Americans may have left Afghanistan already.

Some may have returned to the States but others may have gone to third countries.

At the Pentagon, Mr Kirby declined to say whether defence secretary Lloyd Austin had recommended to Mr Biden that he extend the August 31 deadline.

Given the Taliban’s takeover of the country, staying beyond that date would require at least the Taliban’s acquiescence, he said.

He said he knew of no such talks yet between US and Taliban commanders, who have been in regular touch for days to limit conflict at the airport as part of what the White House has termed a “safe passage” agreement worked out on Sunday.

Hoping to secure evacuation seats are American citizens and other foreigners, Afghan allies of the Western forces, and women, journalists, activists and others most at risk from the fundamentalist Taliban.

Will US troops go beyond the airport perimeter to collect and escort people?

Mr Austin suggested on Wednesday that this was not currently feasible. “We don’t have the capability to go out and collect large numbers of people,” he told reporters.

Afghans in danger because of their work with the US military or US organisations, and Americans scrambling to get them out, also pleaded with Washington to cut the red tape that has complicated matters.

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