Justice Minister Tzipi Livni, who heads the Israeli-Palestinian peace negotiations alongside Prime Minister Benjamin Netanyahu's envoy Yitzhak Molcho, is set to review the cases of more than 100 terrorists imprisoned in Israel, whose releases are sought by the Palestinian Authority. The terrorists were tried and sentenced by Israel prior to the signing of the 1993 Oslo Accords. "These are heinous terrorists who committed atrocious crimes," Livni said Saturday. She did not elaborate on whether the U.S. was pushing for the review, or whether the PA's demand was a precondition for renewing peace talks. U.S. Secretary of State John Kerry, who visited Israel last week -- his fourth visit in two months -- said Friday, "We are reaching the time where leaders need to make hard decisions." He urged Netanyahu and PA President Mahmoud Abbas to show leadership, warning, "It is clear that in the long run the status quo is not sustainable." Kerry also announced that Gen. John Allen, the former commander of U.S. and NATO forces in Afghanistan, would be joining the Israel-PA negotiation efforts. Meanwhile, President Shimon Peres is visiting Jordan, representing Israel in the World Economic Forum on the Middle East and North Africa. Peres will meet with various Arab leaders who are attending the conference, including Abbas and Jordan's King Abdullah II. Peres and Netanyahu held an extensive meeting on Friday at the President's Residence in Jerusalem, in which the issues the president will raise during his meetings in Jordan were discussed.