Afghans on Wednesday faced an increasingly desperate race to escape life under the Taliban after U.S. President Joe Biden confirmed his country's evacuations will end next week.

More than 70,000 people have already been evacuated, but huge crowds remain outside Kabul Hamid Karzai International Airport hoping to flee the threat of reprisals and repression in Taliban-ruled Afghanistan. Biden said Tuesday the United States would stick to his Aug. 31 deadline to completely withdraw its troops despite warnings from European allies that not all vulnerable Afghans would be able to leave by then.

"The sooner we can finish, the better ... each day of operations brings added risk to our troops," Biden said Tuesday. "We are currently on the pace to finish by Aug. 31."

Biden acknowledged that the airlift depends on continued cooperation with the Taliban as well as access to the airport with no disruption to operations. He also underlined that he has asked the Pentagon and the state department for "contingency plans to adjust the timetable should that become necessary."

"I’m determined to ensure that we complete our mission, this mission. I’m also mindful of the increasing risks that I’ve been briefed on and the need to factor those risks in," Biden said according to the British newspaper Guardian.

Many Afghans fear a repeat of the brutal five-year Taliban regime that was toppled in 2001. There is the real threat of violent retribution for working with foreign militaries, Western missions and the previous U.S.-backed government. Washington and its allies have been flying out thousands of such Afghans every day on hulking military transports, but it has become an increasingly difficult and desperate task.

The airport in Kabul has been gripped by chaos as U.S.-led troops try to maintain a secure perimeter for evacuation flights, surrounded by desperate Afghans. Some have foreign passports, visas or eligibility to travel, but most do not. At least eight people have died in the chaos.

"Does anyone ... ANYONE ... have a contact inside the airport," pleaded one American on a WhatsApp group set up to share information on how people can access the airport. "My guy worked for us 2010-15 and needs to get out with 5 of his family. This is real bad."

The Taliban have also been accused of blocking or slowing access for many trying to reach the airport, although they denied the charge again late Tuesday. Biden said the Taliban were taking steps to assist, but there was also an "acute and growing risk" of an attack by the regional chapter of the Daesh terrorist group.

CIA Director William Burns flew to Kabul for a secret meeting with top Taliban leader Abdul Ghani Baradar, U.S. media reported Tuesday, the highest-level meeting so far between the U.S. government and the new rulers of Afghanistan. The New York Times said the spy chief was not there to negotiate an extension to the pullout deadline, but for general talks on "evacuation operations and terrorist threats."

'It will not be enough'

Despite the harrowing scenes at Kabul airport, the Taliban have ruled out any extension to next Tuesday's deadline to pull out foreign troops, describing it as "a red line."

"They have planes, they have the airport, they should get their citizens and contractors out of here," Taliban spokesperson Zabihullah Mujahid said Tuesday.

European nations have said they would not be able to airlift all at-risk Afghans before August 31.

"Even if (the evacuation) goes on ... a few days longer, it will not be enough," German Foreign Minister Heiko Maas told Bild TV. A hard withdrawal deadline presents a further complication that may reduce the number of daily evacuations.

The United States deployed fresh troops for evacuations. That 6,000-plus contingent, as well as hundreds of U.S. officials, 600 Afghan troops and the equipment, will have to be flown out. To do that by Aug. 31, the Pentagon said operations would have to start winding down days in advance.

Taliban urge Afghans to stay

Following their lightning victory that stunned the world, the Taliban have so far been content to allow the U.S.-led operation to continue, focusing instead on consolidating control and forming a government. They have vowed a softer, more inclusive regime this time around, offering amnesty to opponents and assurances of rights to women. But many Afghans remain fearful and skeptical.

In an attempt to assuage fears, the Taliban spokesman on Tuesday urged skilled Afghans to not flee, saying the country needed "expert" Afghans such as doctors and engineers. But Mujahid added that women who work for the Afghan government should stay home until the security situation improves. The Taliban have said women will be able to get an education and work, but within bounds.

Meanwhile, British Prime Minister Boris Johnson said Tuesday the G-7 will not recognize the Taliban's new government unless it gives guarantees that people will be able to leave the country, both before and after the Aug. 31 deadline.

As Biden rejected pleas of domestic and international allies, top Republican lawmakers in the U.S. House of Representatives introduced a resolution denouncing Biden's "failure to heed the advice of military and intelligence advisors about the speed and nature of the Taliban offensive." The resolution demonstrated growing opposition in the legislature to Biden's approach in Afghanistan and that the withdrawal will be politically costly for the president.