Taliban fighters manned checkpoints around Kabul's airport on Thursday as concerns built they were blocking Afghans from reaching evacuation flights, with the United States demanding safe passage.
Tens of thousands of people have tried to flee Afghanistan since the hardline Islamist militants swept into the capital on Sunday, completing a stunning rout of government forces and ending two decades of war.
Taliban leaders have in recent days repeatedly vowed not to seek revenge against their opponents, while seeking to project an image of tolerance.
They have also sort to portray growing political authority, with Taliban co-founder Mullah Abdul Ghani Baradar returning from exile and other senior figures meeting ex-president Hamid Karzai.
But the United States said Wednesday the Taliban were reneging on pledges to allow Afghans who worked with the United States and its allies out of the country.
"We have seen reports that the Taliban, contrary to their public statements and their commitments to our government, are blocking Afghans who wish to leave the country from reaching the airport," Deputy Secretary of State Wendy Sherman told reporters.
"We expect them to allow all American citizens, all third-country nationals and all Afghans who wish to leave to do so safely and without harassment."
- Desperate to leave -
Taliban spokesman Zabihullah Mujahid said Tuesday that the new regime would be "positively different" from their 1996-2001 stint.
Their rule then was infamous for an ultra-strict interpretation of Sharia law, featuring deaths by stoning, girls being banned from school and women from working in contact with men.
The United States ultimately led the invasion of Afghanistan to topple the Taliban because they continued to provide sanctuary for Al-Qaeda after the September 11 attacks.
"I am desperate to leave, I have bad memories of their regime," a 30-year-old person who worked for a foreign NGO and tried but failed to reach Kabul airport on Wednesday told AFP.
"They hate people who have worked for other agencies rather than their movement."
The person recounted hearing shots being fired, and crowds of people trying to reach the airport.
"Despite that (the shooting) people were moving forward just because they knew a situation worse than death awaited them outside the airport."
The United States said it had airlifted out nearly 5,000 US citizens and Afghans, while France, Britain and other nations have also organised evacuation flights.
But the Taliban have not been solely to blame for Afghans being unable to flee.
The Netherlands said Wednesday its first evacuation flight returned without a single Dutch or Afghan national as US troops blocked them from entering the airport.
At the start of the week, before the US military took greater control at the airport, there were scenes of tragic desperation with mobs of people trying to board planes.
Some footage showed hundreds of people running alongside a US Air Force plane as it rolled down the runway, with some clinging to the side of it.
One person was later found dead in the wheel well of the plane.
- Political authority -
President Joe Biden -- under pressure at home and abroad over his handling of the withdrawal of US forces after 20 years of war -- said Wednesday that some soldiers could remain past the August 31 deadline to ensure all Americans get out.
In an interview with ABC News, Biden also issued another defence of the withdrawal.
"The idea that somehow there's a way to have gotten out without chaos ensuing, I don't know how that happens," Biden said in an ABC News television interview.
On the political front, the Taliban continued to edge towards establishing a government, meeting with senior Afghan figures from the past two decades.
Taliban negotiator Anas Haqqani met with Karzai, the first Western-backed leader of Afghanistan after the Taliban's ouster in 2001, and Abdullah Abdullah, who had led the government's peace council, the SITE monitoring group said.
In the United Arab Emirates, ousted president Ashraf Ghani -- who fled on Sunday as the insurgents closed in on the capital -- said he supported negotiations between the Taliban and former top officials, and was in his own talks to return home.
But Sherman said Ghani was "no longer a figure" on the country's complex political stage.