Prince Turki al-Faisal told a conference on Washington's relations with the Arab world that the United States was the only nation with the power to jolt the stalled international roadmap to Middle East peace into motion.
"We want you to remain friends with Israel, we have no objection to that," Prince Turki said.
"But that friendship should be used to push Israel to engage in the peace process," he added, rejecting arguments that political conditions in the volatile region were currently too inflamed to permit negotiations.
"These excuses will continue ... we have heard them for the last 50 years," Prince Turki said.
"Implementation should be done now. The United States devised the roadmap, it needs to implement it," he said.
"The United States is the only country that can do the right thing for everybody in the Middle East," Prince Turki told the conference of the National Council on US-Arab Relations.
"The United States has been engaged and enmeshed in our political situation for the last 50 years or so, whether it likes it or not," he said.
The Bush administration has been less willing than many of its predecessors to engage in nuts and bolts peacemaking between Israel and the Palestinians -- despite calling for the formation of a Palestinian state.
US Secretary of State Condoleezza Rice returned from her sixth visit to Israel and the Palestinian territories earlier this month, but failed to break the peacemaking stalemate.
The process has been frozen since the radical Islamic movement Hamas, which refuses to accept Israel's right to exist and is listed as a terrorist organisation by Europe and in Washington, won legislative elections in January and gained control of the Palestinian government.
The international "roadmap" to peace was designed by the so-called Middle East quartet of the United States, Russia, the European Union and the United Nations.
It was announced in 2003, with the aim of establishing by 2005 a viable Palestinian state living alongside Israel in peace.

Copyright AFP (Agence France-Presse), 2006