Palestinian negotiator Saeb Erakat says that Israel will free the first batch of a promised 104 long-serving Palestinian and Israeli Arab prisoners on August 13.
"The release of veteran prisoners will be in four batches as Israel refused to release them all at once," he said in a statement.
Israel says that the men will go free in stages depending on progress in newly-resumed peace talks with the Palestinians.
"It agreed on releasing 26 of the old prisoners on August 13," Erakat said in the statement, released on Saturday.
The prisoner release was approved by the Israeli cabinet last week to coincide with the talks, revived after a three-year hiatus.
A first meeting took place in Washington earlier in the week and the Israeli negotiator, Justice Minister Tzipi Livni, said on Saturday that another session would be held shortly in the Middle East.
"These discussions that began in Washington will resume during the second week of August and will take place in the region," Livni told the private Channel 10 television station.
She said the talks would alternate between Israel and the Palestinian territories, and that the first of 104 prisoners imprisoned by Israel prior to the 1993 Oslo peace accords would be freed before the next round.
The names of the prisoners to go free have yet to be officially published, but they reportedly include many militants convicted of killing Israelis.