Olmert agreed to the prisoner release earlier this month as a goodwill gesture after talks with Palestinian Authority President Mahmoud Abbas, and the Israeli cabinet codified the deal with a 16-4 vote, a source told CNN.
Palestinian negotiator Saeb Erakat told the broadcaster the prisoner release was set for Aug. 25.
Jailed Fatah leader Marwan Barghouti would not be among the among freed prisoners, CNN said.
Olmert has announced his plans to resign as prime minister in September.
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