Jawed Faisal, spokesman for the Afghan National Security Adviser's office, said the releases were being delayed because more time was needed to review the list of prisoners. The move comes despite President Ashraf Ghani's decree earlier this week promising the start of the releases Saturday as a good will gesture to get intra-Afghan negotiations started.
The U.S.-Taliban deal was touted at the time as the best chance at ending Afghanistan's endless wars and bringing U.S. troops home after nearly 19 years.
There was no immediate response from the Taliban to the delayed prisoner release.
Faisal said Ghani's government wanted more time to review the list of prisoners. The U.S.-Taliban deal called for the release of up to 5,000 Taliban as well as 1,000 Afghan government captives ahead of intra-Afghan negotiations, considered a critical next step to reaching a lasting peace in Afghanistan.
Ghani's decree promised the release of 100 prisoners a day beginning Saturday until 1,500 prisoners were released. He would then release the remaining 3,500 after intra-Afghan talks began and those releases would be staggered and would go ahead only if talks progressed and Taliban reduced violence.
Although Ghani's decree differs from the U.S.-Taliban deal, Faisal insisted Ghani was committed to releasing 5,000 Taliban prisoners.
However, Ghani is embroiled in political turmoil in Kabul, where he is battling his leading political rival Abdullah Abdullah, who has also declared himself president. Abdullah has so far refused to accept the results of last year's presidential results charging widespread irregularities and abuse of power by Ghani. Still, the national election commission last month declared Ghani the winner despite allegations lodged also by the elections complaints commission.
Meanwhile, the decree Ghani announced on Wednesday said the first round of 1,500 prisoners to be freed would be selected based on age, health and the length of their sentences already served. The released prisoners, who would be biometrically identified, would also have to give a written guarantee that they would not return to the battlefield.
The Taliban handed off their list of 5,000 to an American negotiator, who delivered it to the Afghan government administration. The Taliban's spokesman in Qatar, where the insurgent group maintains a political office, said the Taliban would accept only those on the pre-approved list and warned Kabul against offering substitutes.
The Taliban said they are committed to the deal they made with the United States but would not start negotiations with Kabul government or other political leaders until the prisoners were freed.
Even if the Taliban were ready to talk, it's not clear when Kabul would be ready to field a negotiating team as the feud between opposing politicians has yet to be resolved.
The United States has said its withdrawal of troops — which has already begun — was not dependent on successful negotiations between Afghans on both sides of the conflict.
However, the U.S. State Department has issued statements urging Kabul's feuding politicians to find a compromise, urged an end to "posturing" and said many of the Taliban prisoners on the list had already served their sentence and that the names were decided after lengthy negotiations.
Washington also chastised the Taliban for resuming attacks on Afghanistan's security forces, even though they promised not to attack U.S. and NATO troops. Washington said the level of Taliban violence was too high and wanted to see a reduction.
Despite the political chaos in Kabul and increased violence on the battlefield, the United States has started withdrawing its troops in keeping with the deal it signed Feb. 29 with the Taliban. In the first phase, Washington will reduce its troops contingent to 8,600, down from the current 13,000.
If the Taliban adhere to their commitments to deny terrorists safe havens in Afghanistan, Washington will withdraw the remainder of its troops over 14 months, according to the agreement.