Miller, who is acting head of the Pentagon until President-elect Joe Biden takes office next month, and Ghani discussed the ongoing talks with the Taliban, which the Defense Department said in a statement were a "historic opportunity" to achieve peace in the war-torn country.

Miller also met with the head of US forces in Afghanistan, General Scott Miller, "to gain his assessment of the overall security situation to include the current counterterrorism and Train, Advise and Assist missions, the level of Taliban violence and the ongoing drawdown of US forces," according to the statement.

Eager to put an end to America's "endless wars," the outgoing Republican President Donald Trump decided to reduce the US military presence in Afghanistan to 2,500 troops by January 15.

The move accelerates a timeline the US agreed on in an earlier deal with the Taliban, which provides for total withdrawal of American forces by May 2021 in exchange for security guarantees.

The US military had some 13,000 troops in Afghanistan a year ago and had reduced the level to 4,500 as of November.

The Pentagon had been eager to maintain at least 4,500 troops in Afghanistan in the new year amid the peace talks, but officials say the military is complying with Trump's order.

However, Afghanistan is experiencing an upsurge in violence, with the Taliban carrying out almost daily attacks against government forces in recent weeks.

It is not certain that a new Democratic administration will accept the full withdrawal under the terms of the agreement struck between Washington and the Taliban earlier this year in Doha, Qatar.

At least five people, including four doctors working in a prison where hundreds of Taliban are being held, were killed Tuesday in Kabul when a bomb attached to their car exploded.

Last week, US Chief of Staff General Mark Milley traveled to Doha to urge the Taliban to reduce violence in Afghanistan.