Rice arrives Monday in Saudi Arabia for talks with King Abdullah, then flies to Egypt for a day of meetings before heading to Israel and the Palestinian territories.

The US came under strong pressure to take a more active role in trying to revive Israeli-Palestinian peace talks after being seen to favor Israel too heavily in its devastating response to attacks by the Lebanese militia Hezbollah in July.

European and moderate Arab allies, whose support is key to US plans for Iraq, Lebanon and Iran, see the festering Israeli-Palestinian stalemate as feeding instability and radicalism across the region.

But Washington's main allies in relaunching the process, Palestinian president Mahmud Abbas and Israeli Prime Minister Ehud Olmert, are seen as too politically weak at home to guarantee the concessions both sides need to make to reach their goal of creating a stable Palestinian state.

Abbas, a soft-spoken businessman who has never achieved the authority of the late Palestinian leader Yasser Arafat, has been undermined by the victory in Palestinian elections early this year of the radical Islamic movement Hamas.

The group, which still officially seeks Israel's destruction, took control of the Palestinian legislature in March, prompting Israel, the US and Europeans to cut essential financial aid to the West Bank and Gaza Strip.

Abbas has been trying to draw Hamas into a unity government that would meet international conditions of recognizing Israel's right to exist, rejecting violence and accepting past peace agreements.

But so far the Islamic group has balked.

Olmert has also been unable to fill the shoes left empty when his predecessor, Ariel Sharon, was felled by a massive stroke in January.

His political standing plummeted following the war in Lebanon, in which Israel's once all-powerful military was unable to inflict a clear defeat on Hezbollah guerrillas despite a destructive month-long air and ground offensive.

Under attack for his conduct of the war, Olmert has shelved a plan to move ahead with the Palestinians by withdrawing from parts of the West Bank following a similar pullout from Gaza last year.