TEL AVIV — US Secretary of State John Kerry wound up his most intensive push yet for a revival of Middle East peace talks Sunday without achieving a breakthrough, but he said that his four days of marathon meetings with Israeli and Palestinian leaders had yielded “real progress” and that a resumption of substantive negotiations could be “within reach.” He said he would return to the region soon. “We started out with very wide gaps and we have narrowed those considerably,” Kerry told reporters at Ben Gurion International Airport before flying to Asia for a meeting of foreign ministers. “We have made real progress on this trip and I believe that with a little more work the start of final-status negotiations could be within reach.” “I am very hopeful that we are close to an approach that will work, but it will take a little bit more time to work through some of the details and modalities,” Kerry added. “I am absolutely confident that we are on the right track and that all of the parties are working in very good faith.” Kerry's comments came after a hectic weekend of shuttle diplomacy. He canceled a scheduled stop in the United Arab Emirates to press Israeli Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas to return to the negotiating table after years of stalemate. He met three times with each leader and their top aides, including a six-hour session in occupied Jerusalem that ended at 3:30 a.m. Sunday. Later, he drove to the West Bank for a two-hour talk with Abbas at his headquarters in Ramallah. The chief Palestinian negotiator, Saeb Erekat, described the meeting as “positive and profound,” but, he added, “there has been no breakthrough so far and there is still a gap between the Palestinian and Israeli positions.” Netanyahu had earlier told his cabinet, “Israel is prepared to enter negotiations without delay, without preconditions.” “There are things that we will stand on with strength in these discussions, the first of which is security,” the prime minister said. “We will not compromise security and there will not be any agreement that will endanger the security of citizens of Israel.” The sticking points for bringing the parties back to the table are familiar: Abbas is insisting on a freeze of the building of Jewish settlements in the West Bank, the release of some 120 Palestinians who have been in Israeli prisons for more than 20 years and the use of the pre-1967 borders as the basis of negotiations. Israeli newspapers reported Sunday that Netanyahu had expressed a willingness to release prisoners but only in stages, and to freeze settlement construction, but only outside of three large blocs he says must remain part of Israel. There are also indications that both sides might accept an American statement on the 1967 borders, along with one about Israel being a Jewish state, allowing the parties to avoid having to say it themselves. But even as Kerry worked around the clock, controversy continued over settlement building. A hearing is scheduled for Monday regarding a new neighborhood of 930 apartments in the Har Homa area of southern Jerusalem that Israel annexed after the 1967 war. Har Homa is considered an illegal settlement under international law, and this development is particularly problematic for the Palestinians because it would separate Bethlehem, in the West Bank, from other parts of East Jerusalem. Netanyahu's government has not started any new settlement projects during Kerry's three-month push for peace talks, but it has allowed approved developments to move closer to construction. — Agencies