Indyk was ambassador to Israel from 1995 to 1997 and is a key player in the U.S. team working on Middle East peace. In his current job he has a wider responsibility for diplomatic activity with the whole region.

"Ambassador Indyk has a wealth of experience with peace-process issues and longstanding ties with key Israeli and Arab officials," State Department spokesman James Foley told reporters after announcing the switch.

He noted that Clinton's national security adviser, Sandy Berger, had emphasized in a speech last week "the potentially fleeting nature of this opportunity to close the circle of peace in the Middle East."

The switch reflected a consciousness on the part of Clinton that "indeed this is a window that will not be open forever and the parties in the region have indicated their eagerness to seize the opportunity that exists over the next 12 months or so to really try to reach final agreements," Foley said.

In Jerusalem, a U.S. diplomatic source said Indyk would visit Israel with U.S. Middle East Coordinator Dennis Ross this week to review the Israeli-Palestinian talks and to begin preparing for the Nov. 2 summit in Oslo.

Other high-ranking U.S. visitors slated to visit Israel in the coming weeks include First Lady Hillary Clinton, Secretary of Defense William Cohen, and Deputy Secretary of Treasury Stuart Eizenstat.