JERUSALEM -- Prime Minister Benjamin Netanyahu of Israel announced Saturday that he had agreed to release 104 Palestinian prisoners, most of whom have served 20 years or more for attacks on Israelis, to pave the way for a resumption of Israeli-Palestinian negotiations in Washington in the coming days.
Mr. Netanyahu took the unusual measure of issuing what he called "an open letter to the citizens of Israel" to explain the contentious move, which many Israelis oppose, ahead of a cabinet vote on Sunday.
Reports of a prisoner release had been circulating for weeks, but this was the first confirmation by the prime minister of the number expected to be freed. Mr. Netanyahu's letter did not give any details regarding the identities of those to be released or the timing, but said the release would be carried out in stages after the start of negotiations and in accordance with their progress.
The talks were expected to begin Tuesday after months of intense shuttle diplomacy by Secretary of State John Kerry.
Mr. Netanyahu began his letter, which was posted on the prime minister's Web site and disseminated through the Israeli news media, with an acknowledgment of the unpopularity of the gesture, which many Israelis view as a painful concession with nothing guaranteed in return.
"From time to time prime ministers are called on to make decisions that go against public opinion -- when the matter is important for the country," he wrote. He added that the decision "is painful for the bereaved families, it is painful for the entire nation, and it is also very painful for me. It collides with the incomparably important value of justice."
On Friday, Yediot Aharonot, an Israeli newspaper, published an impassioned open letter to Mr. Netanyahu from Abie Moses, whose pregnant wife and 5-year-old son, Tal, were fatally burned in a firebomb attack on their car in April 1987. Mr. Moses said that faced with the likely release of their killer, Mohammad Adel Hassin Daoud, "the wounds have reopened; the memories, which we live with on a daily basis, turn into physical pain, in addition to the emotional pain of coping daily with the nightmare."
Mr. Moses added, "In our opinion, if his release will lead to attaining of peace, let him be released outside the boundaries of Palestine, exiled and never allowed to see his family members again, just as we cannot see ours."
Over the years, thousands of Palestinian prisoners have been exchanged for Israeli soldiers who had been taken captive, or for the bodies of abducted soldiers. During his previous term in office, Mr. Netanyahu reached an agreement with Hamas, the Islamist militant group that governs Gaza, and exchanged more than 1,000 Palestinian prisoners for Gilad Shalit, an Israeli soldier who had been held captive in Gaza for five years.
An Israeli government official, speaking on the condition of anonymity because he was not authorized to discuss the matter publicly, said many of those who remained in Israeli jails, like the 104 now chosen for early release, had been involved in particularly gruesome acts.
"The goal here is to augment the political dialogue with confidence-building measures," the official said, adding that the cabinet was expected to approve the release. In moves meant to appease the more right-wing elements in the government, the cabinet is also expected to discuss legislation for a referendum on any peace deal and to set up a special ministerial committee to deal with the negotiations.
But the prisoner issue is the one that has inflamed passions on both sides. Palestinians view these long-serving prisoners, convicted before the signing of the Oslo peace accords in 1993, as political prisoners whose release is long overdue.
A Palestinian official involved in the negotiations process, who could speak only on the condition of anonymity because of the delicate diplomacy under way, said the Palestinian side had given a list of all 104 pre-Oslo prisoners to Mr. Kerry, who conveyed it to the Israelis. Israel had previously balked at including 22 prisoners who are Arab citizens of Israel or residents of East Jerusalem. Israeli officials have so far refused to say whether those objections have been dropped.
"This is the biggest achievement we will have had this year," the Palestinian official said.
He said the first group was expected to be released in August, and the rest within six months.
This article originally appeared in The New York Times.