He said both Netanyahu and Abbas had asked him to return to the region — on what would be his sixth visit. But he declined to disclose, even broadly, the main elements of the "package" being pursued to restart talks.
Kerry said it was best not to float ideas for others to "tear apart, evaluate and analyze." He said he would not have agreed to leave his staff in place if he didn't think it was possible to flesh out a "serious" framework for restarting discussions.
"I think this is worth it, folks," he told reporters. "Obviously, the work has to be completed. People have to make a few choices still. But the gap has been narrowed very significantly."
A Palestinian official who was briefed on Kerry's efforts said the package would likely include, as a goodwill gesture, the release of some Palestinian prisoners held by Israel. He said the Palestinians were told that Netanyahu is prepared to restrain settlement construction and to discuss the 1967 borders, without any promise to withdraw to those lines. The official spoke on condition of anonymity because he was not authorized to discuss the matter with the media.
The emerging deal is also expected to include large amounts of international aid to the Palestinians; Israeli agreement to allow the Palestinians to launch new development projects in the West Bank; and Palestinian pledges to halt their campaign of seeking recognition of their independence in international bodies before there is a peace agreement.
Over Israeli and U.S. objections, the Palestinians last year won upgraded observer status at the United Nations, and they have threatened to pursue war crimes charges against Israel if peace efforts remain stalled.
Israel's Channel 2 TV, citing anonymous Israeli officials, said there had been progress, but sticking points remained in the areas of settlements, prisoners and borders. It said Kerry was expected back in a week or so and was aiming to restart talks before the Muslim holiday of Ramadan begins early next week.
Addressing his Cabinet on Sunday, Netanyahu showed little signs of bending.
"We are not putting up any impediments on the resumption of the permanent talks and a peace agreement between us and the Palestinians," he said.
At the same time, he said, "We will not compromise on security, and there will be no agreement that will endanger Israelis' security."
He added that any agreement would be presented to the public in a referendum.
Critics have said such a step would merely add an additional obstacle to implementing any deal, which would require a broad pullout from the West Bank.
Following Sunday morning's meeting in Ramallah, the chief Palestinian negotiator, Saeb Erekat, reported progress but said gaps remained.
"I cannot say we have a breakthrough," he said. "All I can say once again is no one benefits more from the success of Secretary Kerry than the Palestinians, and no one stands to lose more from its failure than Palestinians."
As Kerry strolled to the tarmac Sunday, his top Mideast adviser patted him on the back, but both knew the job was not finished.
Associated Press writer Mohammed Daraghmeh in Ramallah, West Bank, contributed to this report.