Any encounter between Rice and Iranian Foreign Minister Manouchehr Mottaki will not tackle substantive issues, added the official, who asked not to be named.

Rice, Moualem and Mottaki are in the Egyptian Red Sea resort of Sharm el-Sheikh for a two-day meeting on economic recovery in Iraq and its political future.

The U.S. official said that even the meeting between Rice and Moualem would deal mainly with security on the Iraqi-Syrian border, not with Lebanon or attempts to prosecute those who killed former Lebanese Prime Minister Rafik al-Hariri in 2005.

"I would expect they will have a discussion on border security issues," a senior State Department official said.

Asked what Rice would say if Moualem brought up Lebanon or other matters not directly related to Iraq, the official said: "She will restate U.S. policy on these issues."

U.S. officials said that if Rice did exchange words with the Iranian minister in Sharm el-Sheikh it would probably be in passing before dinner.

This would be in accordance with the wishes of the Iranian side, the official said.

Iran and the United States have not had relations since soon after the Islamic revolution in Iran in 1979.