John Kerry, US secretary of state, has left for a series of meetings in Europe seeking to head off an end-of-year UN showdown over a Palestinian bid for statehood.
His first stop on Sunday was to be Rome, where he will meet separately both Sergey Lavrov, Russian foreign minister, and Benjamin Netanyahu, Israeli prime minister.
Diplomats say negotiations on a UN resolution to revive Israeli-Palestinian peace prospects are making little headway, with Europeans waiting for a US response to proposals.
Jordan last month circulated a draft Palestinian text to the Security Council setting November 2016 as a deadline for the end of the Israeli occupation.
But the text ran into opposition from the US, which has veto power, and other countries that felt it lacked balance, diplomats said.
It was never put to a vote.
France stepped in last month to try to draft along with Britain and Germany a resolution that would win consensus at the 15-member council.
The Palestinians have said they would like a draft resolution to go to a vote before the end of the year.
The text would call for a return to negotiations with a view to achieving a two-state solution by which Israel and a Palestinian state would co-exist.
Negotiations have hit hurdles over whether to include a two-year deadline for talks on a final settlement to be completed.
France is also proposing to host an international conference to launch the new peace track.
Kerry met on Thursday with his French counterpart Laurent Fabius on the sidelines of climate talks in Lima, to discuss the tensions in the Middle East.
Supporters of a UN resolution are now hoping to win US backing or at least ensure Washington will not oppose the measure, which would be the first text adopted by the council on the Israeli-Palestinian conflict since 2009.
Kerry is due to meet Lavrov on Sunday, shortly after arriving in Rome.
Russia responded angrily on Saturday to news that US senators had passed a bill calling for fresh sanctions against Moscow and the supply of lethal military aid to Ukraine.
The eight-month conflict in Ukraine between government forces and pro-Russian separatists has left at least 4,634 dead and 10,243 wounded, while displacing more than 1.1 million people, according to the United Nations.
Talks with Netanyahu follow on Monday, after which the top US diplomat is expected to travel on within Europe although no stops have yet been announced.