AFP - US Middle East envoy George Mitchell pledged his country's support for regional peace on Monday when he met Jordan's King Abdullah II, who urged Washington to take a "leading" role in the process.

"Mitchell stressed that the United States is committed to achieving a just and comprehensive peace between Israel and the Palestinians based on a two-state solution," a palace statement said.

"He said Washington will continue to work hard on achieving peace."

The king, whose country signed a peace treaty with Israel in 1994, urged the United States to help create a "suitable environment" for jump-starting Palestinian-Israeli peace talks "in line with a clear timetable," the statement said.

"Washington should assume a leading role in finding a suitable environment to jump-start Palestinian-Israeli peace talks," he was quoted as telling Mitchell.

"The king warned that failing to create peace will affect the stability and security of the entire region."

Abdullah held a separate meeting later with Palestinian president Mahmud Abbas, and warned that Israel's "unilateral measures," mainly settlements in the occupied West Bank, "obstruct peace efforts," the palace said.

Washington has struggled for months to revive peace talks, but has made little visible progress.

The issue of Israeli settlements on Palestinian land, considered illegal by the international community, is considered to be the main stumbling block.

US Secretary of State Hillary Clinton said on Monday Washington still opposes new Jewish settlements in the West Bank.

The United States had urged a total halt to new Israeli construction in the West Bank as a precursor to new negotiations, but on Saturday Clinton said Israeli Prime Minister Benjamin Netanyahu's offer to restrict new building was "unprecedented".

On Monday she said his offer "falls far short of our preferences" but was still worth seizing.

"If it is acted upon it will be an unprecedented restriction on settlements and will have a significant and meaningful effect on restraining their growth," Clinton said ahead of a meeting of Arab foreign ministers in Marrakech, Morocco.