"The two monarchs stressed their rejection of unilateral solutions which Israel is trying to implement in the Palestinian territories," said an official accompanying Jordan's king on a visit to Riyadh.

King Abdullah II started on Wednesday a visit to Saudi Arabia for talks with senior officials, on the eve of a summit with Ehud Olmert, the Israeli prime minister.

The Israeli leader won elections in March on a pledge to set his country's final borders by 2010, unilaterally in case of failure to agree with the Palestinians. That prompted concerns around the Arab world.

The two monarchs called for a resumption of the peace process based on an Arab initiative drawn up by Saudi Arabia in 2002 and the international roadmap peace plan, the Jordanian official said.

They also called on Palestinian factions to "discard disputes and protect national unity", he added, in reference to clashes between the former ruling Fatah movement and the government led by the Islamist movement Hamas.

King Abdullah's visit to Saudi Arabia was the latest in a flurry of Arab diplomatic moves which analysts say are aimed at reviving peace talks between Israel and the Palestinians to head off Israeli plans for a unilateral deal.

Last week, the Saudi monarch and Hosni Mubarak, the Egyptian president called on Hamas to adopt the Arab plan to normalise ties with Israel.

Israel's prime minister is due in Amman on Thursday for talks with the Jordanian king.