U.S. diplomats Dennis Ross and David Hale were due in the region later Wednesday, and will meet with Israeli leaders before travelling to the West Bank the next day to talk with Palestinian President Mahmoud Abbas.
Washington is trying to persuade the Palestinians to drop their plan to ask the United Nations to recognize an independent Palestinian state, but so far without success. The Palestinians are turning to the UN after peace talks with Israel broke down, hoping a UN bid would best boost their statehood campaign.
They say they will bring a resolution before the UN during the annual General Assembly session that begins in New York on Sept. 20, in the hope that a UN recognition would enable them to gain leverage with Israel in future negotiations.
Israeli-Palestinian talks stalled nearly three years ago, reviving only briefly last September before foundering again over a Palestinian demand for a full Israeli settlement construction freeze.
Israel opposes the Palestinians' bid to seek UN endorsement of a state in the West Bank, Gaza Strip and east Jerusalem. Foreign Minister Avigdor Lieberman warned Wednesday it would have unspecified "grave implications."
The United States has promised to veto the bid if it reaches the Security Council, whose approval is needed for membership as a full member state. Both Israel and the U.S. contend that negotiations are the only way to produce a Palestinian state.
The Palestinians have not announced what they plan to do at the UN, but they could sidestep the Security Council by asking the General Assembly to grant them the status of non-member observer -- a lesser status than full membership, but an alternative that could not be vetoed by the U.S. and would be expected to pass.
In addition to the U.S. diplomatic efforts, the European Union's foreign policy chief, Catherine Ashton, was making the rounds in Israel on Wednesday, after meeting with Abbas in Cairo a day earlier.
Tony Blair, the special envoy of the Quartet of Mideast mediators -- the U.S., E.U., Russia and the United Nations -- met with Israeli Prime Minister Benjamin Netanyahu on Tuesday and will see Abbas in Amman, Jordan, late Wednesday or Thursday. The Quartet is trying to fashion a statement that would allow both sides to resume negotiations.
The Palestinian bid for recognition comes at a particularly volatile time for Israel and its neighbours. Turkey recalled its ambassador earlier this month after Israel refused to apologize for its May 2010 raid on a Gaza-bound flotilla that killed nine Turks.
Israel's ties with Egypt have been tested by last weekend's attack on the Israeli Embassy in Cairo that forced the evacuation of all Israeli diplomats but one from the country. Friction also flared over the deaths of six Egyptian soldiers, killed as Israeli troops pursued militants who killed eight Israelis shortly after crossing into Israel from Egypt.
A UN report released Wednesday praised state-building achievements by Abbas' government but warned they were at risk because of the stagnant political process.
"The reality is that there is only so much that can be done in conditions of prolonged occupation, unresolved final status issues, no serious progress on a two-state solution and a continuing Palestinian divide," said Robert Serry, the special UN envoy to the Mideast.
Abbas' Palestinian Authority governs the West Bank, but lost control of the Gaza Strip to Hamas militants in 2007. A reunification pact signed in May between the Palestinian factions has not been carried out.
Abbas loyalists are planning two major sets of demonstrations in connection with the UN bid, the first during the launch of the UN session and the second to coincide with Abbas' speech at the General Assembly on Sept. 23. The Palestinians say they are determined to keep the rallies peaceful.
"We want to tell world leaders that the Palestinian people seek freedom and independence and need your support," said Amin Maqboul, a senior official with Abbas' Fatah Party.
The rallies will take place inside West Bank towns and cities, and avoid Israeli military checkpoints and any other flashpoints like entrances to Israeli settlements. Police will ring towns and cities to prevent any clashes with the Israelis, Maqboul said.
"Violence plays into the hands of the Israelis, not ours," Maqboul said.
Israeli security officials are concerned that isolated incidents could touch off more widespread unrest. Soldiers and police have been training for months in preparation for possible violence.