Kathy Gannon and Rahim Faiez

Associated Press

KABUL, Afghanistan – The U.S. military said Tuesday it began withdrawing troops, taking a step forward on a peace deal with the Taliban, and officials praised Afghan President Ashraf Ghani for promising to release Taliban prisoners after he had delayed for more than a week.

The U.S.-Taliban deal signed Feb. 29 is part of Washington’s effort to end 18 years of war in Afghanistan. The next crucial step would be intra-Afghan talks in which all factions, including the Taliban, would negotiate a road map for their country’s future.

Ghani and his main political rival, Abdullah Abdullah, were each sworn in as president in separate ceremonies Monday. Abdullah and the elections complaints commission charged fraud in last year’s vote. The dueling inaugurations threw plans for talks with the Taliban into chaos, although Ghani said Tuesday that he would put together a negotiating team.

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The disarray in the Afghan government is indicative of the uphill task facing Washington’s peace envoy Zalmay Khalilzad as he tries to get Afghanistan’s bickering leadership to come together. In a tweet early Tuesday, Khalilzad said he hoped the two leaders could “come to an agreement on an inclusive and broadly accepted government. We will continue to assist.”

Sonny Leggett, the U.S. military's spokesman in Afghanistan, said in a statement that the military began its “conditions-based reduction of forces to 8,600 over 135 days.”

The United States has about 13,000 soldiers in Afghanistan – 8,000 of whom are involved in training and advising Afghanistan’s National Security Forces, while about 5,000 are involved in anti-terror operations and militarily supporting the Afghan army when they are requested.

Ghani had been dragging his feet on releasing about 5,000 Taliban prisoners, something agreed to in the U.S.-Taliban deal. Ghani promised Monday to announce a decree to free the prisoners, after the United States and a number of foreign dignitaries backed his claim to the presidency by sending their representatives to his inauguration.

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U.S. Secretary of State Mike Pompeo released a statement Monday saying, “We also welcome President Ghani’s announcement that he will issue a decree March 10 on Taliban prisoner release.”

Taliban officials said late Monday that a flurry of biometric identifications were conducted on Taliban prisoners, hinting at a mass release, according to prisoners in lockup. The Taliban officials spoke on condition of anonymity because they weren’t authorized to talk to the media.

Pompeo said he “strongly opposed” the establishment of a parallel government in Kabul, despite the early signs of one emerging. Abdullah sent his vice presidents to occupy official offices Monday, ahead of Ghani’s plan to send his vice presidents to their offices Tuesday.

Pompeo warned against “any use of force to resolve political differences.” Both candidates – but particularly Abdullah – are backed by warlords with heavily armed militias, underscoring fears they could use force to back their candidate.

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The United States said its partial troop withdrawal over an 18-month period will be linked to the Taliban keeping promises to help fight terror in Afghanistan, not to the success of talks between the Taliban and the Afghan government.

On the weekend, Taliban spokesman Zabihullah Mujahed said the insurgent group was committed to its agreement with the United States and called on Washington to do its part to make sure prisoners are freed.

The Islamic State claimed responsibility for a rocket attack during Ghani’s inauguration ceremony. The terrorist group also claimed responsibility for an attack last week on a gathering of minority Shiites that killed 32 and injured scores. The United States expects the Taliban, which has been battling Afghanistan’s Islamic State affiliate, to further aid in the effort to defeat the terrorists.

Gannon reported from Islamabad. Contributing: Matthew Lee in Washington and Tameem Akhgar in Kabul