KABUL, Afghanistan — At least 18 Taliban prisoners, some of them prominent figures, were released by Pakistan and Afghanistan, with no guarantees that they would not rejoin the insurgency, Afghan and Pakistani officials said Saturday.

Pakistani officials said that they were releasing seven Taliban prisoners to facilitate the peace process, while Afghan officials said they had requested the releases and welcomed the move.

Afghan officials complained, however, that Pakistani officials had backed down on the expected release of one Taliban prisoner, Mullah Abdul Ghani Baradar, formerly the top military commander of the insurgents’ movement. Afghan officials have long sought Mr. Baradar’s release, viewing him as crucial to restarting peace talks.

Separately, Afghan officials confirmed Saturday that the day before they had exchanged 11 Taliban prisoners to obtain the release of a female member of the Afghan Parliament, who had been kidnapped by the insurgents last month, according to an Afghan official involved in the prisoner exchange, speaking on the condition of anonymity because he was not authorized to speak to the news media.