Washington: During a grinding 18-month stretch in the 1990s, US envoy George J. Mitchell crossed the Atlantic more than 100 times in a dogged search for peace between Northern Ireland's Protestants and Catholics.

Even though he is a Catholic, Mitchell persuaded Protestant Unionists of his even-handedness, eventually reaching the "Good Friday" agreement in 1998 to help settle the 800-year dispute.

"He's got this incredible patience to sit there until the deal is done," said Ross K. Baker, a political scientist and former congressional aide. Mitchell, he said, "deserves the iron trousers award."

President Barack Obama hopes that the former Senate majority leader, as his new Middle East peace envoy, is prepared to sit a while longer in an effort to settle the conflict between Israelis and Arabs. The 75-year-old Mitchell is widely considered up for the challenge.

"He understood the wheeling and dealing on the floor of the Senate, and he understood the one lesson that to get people to support something, everybody had to get something out of it," said Reg Empey, a Unionist who was involved in the negotiations and is now a minister in the Belfast government.

Since leaving the Senate in 1995, Mitchell has tried twice to settle the Middle East dispute. Mitchell won a reputation for even-handedness in his first foray into Middle East peacemaking, in 2000 and 2001, when he led a six month fact-finding effort probing the reasons for a convulsion of Palestinian violence.

The Mitchell Commission report gave each side something to like and dislike. The panel urged Israelis to halt all colonist activity and to stop shooting at unarmed demonstrators, while calling on Palestinian authorities to stop violence and punish those who commit it.

"Neither side was entirely happy, and that was a good thing," said Gaith Al Omari, who was then a Palestinian negotiator and is now with the American Task Force on Palestine, a Washington group favouring statehood.

Although his mother was Lebanese, Mitchell has not been active in advocacy groups espousing Arab causes. As a senator, his voting record was considered solidly pro-Israel. He supported foreign aid packages for Israel, and regularly voted against sales of US weaponry to Arab countries.

The Mitchell Commission report, which was ordered up by the Clinton administration in October 2000, was delivered in 2001 to the new Bush administration.

Both the United States and Israel endorsed it. But because violence was continuing, Al Omari said, it was "close to still-born."

Nevertheless, some of its key ideas, such as its plans for step-by-step, reciprocal moves toward negotiations, were incorporated into later US plans for peace.