Afghan security forces stand guard at an Afghan National Army outpost after an attack by Taliban militants, in Kunduz Province, Afghanistan on Wednesday. Photo: AFP

The Afghan government will gradually release 5,000 Taliban prisoners starting this week if the insurgents significantly reduce violence, President Ashraf Ghani's spokesman said early Wednesday, seeking to resolve a dispute that has delayed peace talks between the militants and Kabul.

The announcement came hours after the US said its forces had started pulling out of two bases in Afghanistan, in line with a deal signed between Washington and the Taliban in Doha in February aiming to end America's longest war.

The government will "release 1,500 Taliban prisoners as a gesture of goodwill" starting Saturday, with another 3,500 to be freed after negotiations begin, spokesman Sediq Sediqqi said on Twitter.

The agreement, which will initially see 100 prisoners freed each day, will depend on the Taliban's willingness to significantly limit attacks in the country, he added.

The decision attempts to resolve one of the long-running spats that has stymied potential peace talks between the insurgents and the Afghan government.

Although the Taliban were due to start talks with Kabul on Tuesday, negotiations were delayed because the insurgents' demanded a prisoner release in exchange for 1,000 captives as a prerequisite.

Ghani had refused but Wednesday's decree signaled a softening of his stance, with the condition that none of the released prisoners would return to the frontlines.

According to the decree, after the first 1,500 captives are freed, a further "500 Taliban prisoners will be released every two weeks" once negotiations begin.

US negotiator Zalmay Khalilzad welcomed the announcement and urged the Afghan government and the Taliban to meet "immediately" in Qatar to sort out prisoner details.

The State Department voiced confidence that Afghan peace talks would open soon, saying Ghani was in the process of speaking to rivals and would name a negotiating team "in the coming few days."

The UN Security Council on Tuesday endorsed the US-Taliban deal, a rare step for an agreement involving insurgents.

The Council urged the Afghan government "to advance the peace process, including participating in intra-Afghan negotiations."

Under the US-Taliban deal, foreign forces will leave Afghanistan within 14 months, subject to Taliban security guarantees and insurgents holding talks with Kabul.

AFP