USnational security adviser Jake Sullivan said on Tuesday that theTaliban has vowed toprovide safe passage for civilians to reach the airport inAfghanistan's capital Kabul.
Some 3,200 people have been evacuated by the US military so far, a White House official said, including 1,100 on Tuesday alone, US citizens, permanent residents, and their families on 13 flights.
Washington wants to complete the exodus before its August 31 withdrawal deadline, and thousands of US soldiers were at the airport as the Pentagon planned to ramp up flights of its huge C-17 transport jets to as many as two dozen a day.
"The Taliban have informed us that they are prepared to provide the safe passage of civilians to the airport, and we intend to hold them to that commitment," Sullivan said.
"We believe that this can go till the 31st. We are talking to them about what the exact timetable is for how this will all play out, and I don't want to negotiate in public on working out the best modality to get the most people out in the most efficient way," Sullivan added.
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Sullivan said it is premature to say whether the United States recognizes the Taliban as the legitimate governing power inAfghanistan.
"Right now there is a chaotic situation in Kabul where we don't even have the establishment of a governing authority," Sullivan said. "Ultimately, it's going to be up to the Taliban to show the rest of the world who they are and how they intend to proceed. The track record has not been good but it's premature to address that question at this point."
Sullivan said most people seeking to leaveAfghanistanhave been able to reach the airport, but the United States is addressing with the Taliban some reports of people being turned away.
"This is an hour-by-hour issue, and it's something we're very clear-eyed about, and very focused on holding the Taliban accountable to follow through on its execution," he said.
White House spokeswoman Jan Psaki said there are about 11,000 people inAfghanistanwho have identified themselves as Americans, adding that there may be others "who may not have self-identified who may come and request assistance and come to the airport."
Psaki said the United States is prioritising the evacuation of American citizens, embassy employees and their families, locally employed Afghan staff and holders of and applicants for Special Immigrant Visas (SIVs) available to interpreters and others who assisted the United States inAfghanistan.
Ask what the consequences could be if the Taliban does not stick to its commitment, she said: "The consequences are the full weight and force of the United States military, and I think we've made that clear."
"We're not trusting, we're not taking their word for it. We are watching closely, we are in close contact and we are certainly assessing whether they are going to abide by their commitments," Psaki added.
Army Major General William Taylor, with the USmilitary's Joint Staff, told a news briefing earlier on Tuesday that 4,000 UStroops would be at the airport by the end of the day,an increase of 1,000,and the aim is to have one flight taking off per hour.
(With inputs from agencies)