President Donald Trump's administration has ordered American envoys to seek direct talks with the Taliban to end the country's longest ever war, in a major shift after years of US diplomatic policy on the conflict.

The change in White House stance rolls back a long-held position that any talks must be led and controlled by the Afghan government.

Mike Pompeo, the US Secretary of State, has now told diplomats to seek initial talks with the militant insurgent movement to try to kick start a wider peace process to end the 17-year-long conflict.

The shift marks a significant concession to Taliban demands and comes amid frustration in the White House that Mr Trump's decision last year to ramp up the war has so far yielded few results.

"Our Secretary of State, Mr Pompeo, has said that we, the United States, are ready to talk to the Taliban and discuss the role of international forces," said General John Nicholson, the top US commander in Afghanistan, as he confirmed the news, first reported by the New York Times, on Monday.

"We hope that they realise this and that this will help to move the peace process forward."

Taliban leaders have long said they will not talk with the Kabul government, which they see as a puppet regime, and will instead only talk with America, which ousted the movement from power in 2001.