America's top spy held a secret meeting with the Taliban's de facto leader Abdul Ghani Baradar in Kabul on Monday in the highest-level face-to-face encounter between the two sides since the militant group seized the Afghan capital, a media report said on Tuesday.

The Taliban seized power in Afghanistan on August 15, two weeks before the US was set to complete its troop withdrawal after a costly two-decade war. This forced Afghan President Ashraf Ghani to flee the country to the UAE.

CIA Director William J. Burns held a secret meeting in Kabul on Monday with Baradar in the highest-level face-to-face encounter between the Taliban and the Biden administration since the militants seized the Afghan capital, the Washington Post reported, citing unnamed US officials who spoke on the condition of anonymity,

President Joe Biden's decision to dispatch his top spy, a veteran of the foreign service, comes amid a frantic effort to evacuate people from Kabul international airport in what the president has called "one of the largest, most difficult airlifts in history," the paper said.

The CIA declined to comment on the Taliban meeting but the discussions likely involved the impending August 31 deadline for the US military to conclude its airlift of US citizens and Afghan allies, it added.

The Biden administration is under pressure from some allies to keep US forces in the country beyond August 31 deadline in order to assist the evacuation of tens of thousands of citizens of the US and Western countries as well as Afghan allies desperate to escape Taliban rule.

However, a Taliban spokesman on Monday warned that there will be "consequences" if the US and UK sought an extension to the August 31 deadline for the US-led troop withdrawal from the war-torn country.

Baradar, who spent eight years in Pakistani prison before his release in 2018, has served as the Taliban's chief negotiator in peace talks with the US in Qatar that resulted in an agreement with the Trump administration on the withdrawal of US forces.

In November 2020, he posed for a photo in front of gold-rimmed chairs with then Secretary of State Mike Pompeo.

A close friend of the Taliban's founding supreme leader Muhammad Omar, Baradar is believed to hold significant influence over the Taliban rank-and-file, the paper said.

He fought Soviet forces during their occupation of Afghanistan and was the governor of several provinces in the 1990s when the Taliban last ruled the country.

Since the Taliban's takeover of the country, he has struck a conciliatory tone, saying the militant group is seeking "an Islamic system in which all people of the nation can participate without discrimination and live harmoniously with each other in an atmosphere of brotherhood."

In his meeting with Burns on Monday, Baradar faced one of America's most seasoned diplomats, a former deputy secretary of state who has also served as US ambassador to Russia, the Post said.

In April, Burns made an unannounced trip to Afghanistan as concerns mounted about the Afghan government's ability to fend off the Taliban after the US withdrawal, the paper said.

As director, Burns oversees a spy agency that trained elite Afghan special forces units who had been viewed as a potent force in the country, but were also implicated in extrajudicial killings and human rights violations.

On Monday, before details of the secret meeting emerged, State Department spokesman Ned Price was asked about why senior US officials hadn't engaged with Baradar given the stakes in Afghanistan.

Price said "our discussions with the Taliban have been operational, tactical, they have been focused largely on our near-term operations and near-term goals what is going on at the airport compound that is what we're focused on at the moment."