U.S. Middle East Advisor Dennis Ross to Resign

President Barack Obama's key Middle East advisor Dennis Ross said Thursday he would resign after a period of turmoil in the Arab world and a difficult period in U.S. relations with Israel.

Ross, a veteran U.S. peace negotiator, said in a statement he had made a promise to his wife to return to private life after two years in the administration -- and had outstayed that promise by a year.

Ross said in a statement that he was returning to private life with "mixed feelings."

"It has been an honor to work in the Obama Administration and to serve this president, particularly during a period of unprecedented change in the broader Middle East.

"Obviously, there is still work to do but I promised my wife I would return to government for only two years and we both agreed it is time to act on my promise.

"I am grateful to President Obama for having given me the opportunity once again to work on a wide array of Middle Eastern issues and challenges and to support his efforts to promote peace in the region."

White House spokesman Jay Carney said that Ross, a special assistant to the President, had played a key role at a "historic time in the Middle East and North Africa."

Ross played "a critical role in our efforts to apply unprecedented pressure" on the Iranian government and had also supported democratic transitions in the region, Carney said.

Carney said that Obama would continue to periodically draw on Ross's counsel going forward.

Ross is known as a longstanding and patient negotiator in the Middle East with deep ties with successive generations of Israeli leaders. His critics though have sometimes whispered that he is too close to Israel.

Ross, however, who also served president Bill Clinton, also spent long periods of time with Palestinian leaders, through years of frustrated U.S.-brokered efforts to forge peace between Israel and the Palestinians.

He leaves at another uncertain moment in the history of testy ties between the Obama White House and the government of Israeli Prime Minister Benjamin Netanyahu and at a point where Israel-Palestinian peace talks have shuddered to a halt.

At a G20 summit last week, Obama was party to a conversation in which French President Nicolas Sarkozy called Netanyahu a "liar" and Obama appeared to also be frustrated with the Israeli leader.

"You may be sick of him, but me, I have to deal with him every day," Obama replied in comments that were translated into French and picked up an open microphone.