Kabul has blamed the Taliban for a delay in the exchange of three extremist prisoners held in Afghanistan for two Western hostages that the militant group has been holding.
Afghan President Ashraf Ghani's office on November 16 said the Taliban prisoners "are still being held by the Afghan government."
"The inability of the Taliban to meet the conditions has delayed the exchange process," spokesman Sediq Sediqqi wrote on Twitter, adding that the Afghan government will review the situation and make decisions based "on the country's best interests."
The Western-backed Afghan government did not immediately give specifics on what conditions it believes the Taliban had not met.
Ghani had announced the deal on November 12, saying the Taliban prisoners held at Bagram prison would be "conditionally" released.
The deal was seen by the Afghan government as a key move in securing direct talks with the Taliban, which has so far refused to engage with what it calls a "puppet" regime in Kabul.
The United States has been holding a series of negotiations with Taliban representatives in Qatar over recent years in an attempt to end the 18-year war.
But Taliban spokesman Zabihullah Mujahid on November 15 said the Taliban prisoners to be freed did not show up at an exchange site that had been agreed upon and were still in custody.
Mujahid on November 15 told VOA the deal had been suspended and that it was up to U.S. officials to explain what happened.
"As per the deal with the Americans, our prisoners were to be taken to the mutually agreed safe location and freed there. We would have then released and handed the American [and his colleague] over to them," Mujahid said in a Pashto-language audio message sent to VOA.
The United States did not immediately comment.
The Taliban prisoners were to be swapped for two professors of the American University of Afghanistan in Kabul who had been abducted by gunmen wearing military uniforms in August 2016, U.S. citizen Kevin King and Australian Timothy Weeks.
Mujahid said the Taliban was still holding King, 60, and Weeks, 48.
The Taliban prisoners to be released were Anas Haqqani -- the younger brother of Sirajuddin Haqqani, the leader of the Haqqani network -- and two other prominent militants, Hafiz Rashid Omari and Haji Milli Khan, officials said.
The Haqqani network, known for carrying out brutal attacks in Afghanistan, is part of the Taliban group and is believed to be based in Pakistan.
Afghanistan Blames Taliban For Delay In High-Profile Prisoner Swap