JERUSALEM — Israel has agreed to release some “hard core” Palestinian prisoners as part of U.S. Secretary of State John Kerry’s efforts to restart Mideast peace talks, but it will not meet other Palestinian demands before negotiations resume, an Israeli official said Saturday.

The comments from Yuval Steinitz, Israel’s intelligence and strategic affairs minister, were the first from a senior Israeli official since Kerry announced late Friday that the Israelis and Palestinians will meet soon in Washington to work out the final details on an agreement to relaunch talks that collapsed in 2008.

Kerry’s announcement came after last-minute meetings with Palestinian officials at the end of a day in which he shuttled between the Jordanian capital and the West Bank. He did not offer details, saying that the deal is “still in the process of being formalized.”

Speaking to Israel Radio on Saturday, Steinitz said that as a step toward resuming those talks Israel has agreed to release “hard core prisoners,” including “those that have been sitting in jail for dozens of years.” He did not say how many would be freed, adding only that they would be released in phases.

In Israeli parlance, the term “hard core” refers to prisoners implicated in deadly attacks. Their release has been a long-standing Palestinian demand.