Democratic Rep. Tony Hall of Ohio has been offered a job as ambassador to the United Nations' food and agriculture agencies, government sources said Thursday, and appointment could come as soon as next week.

Hall's office and the White House declined comment on the pending appointment, which was confirmed by sources who spoke on condition of anonymity. The appointment would require Senate confirmation.

Hall's resignation to take the Rome-based post would pave the way for a heavily contested election in the southwestern Ohio district that he has held for 24 years.

Eager to gain a seat in advance of the November elections, Republicans already have conducted a poll to test their chances and are promoting a potential replacement for Hall, former Mayor Mike Turner of Dayton.

"You are looking at a very competitive general election," said Amy Walter, who follows U.S. House races for The Cook Political Report, a Washington newsletter. "When you are talking about just a six-seat margin in having the House or not having the House, Tony Hall's decision to retire is a very big deal."

Democrats have been trying to persuade Hall to stay in the House.

The U.N. position would require Hall to work closely with several food programs, including the Food and Agriculture Agency, International Fund for Agricultural Development and the World Food Programme.

The position has gone unfilled since former South Dakota Sen. George McGovern left in October.

Hall, 60, has served in Congress since 1978. He said at the end of January that he had been talking with the Bush administration for several months about a humanitarian-related job. He declined to comment on the details but said he would decide soon whether to seek re-election to Ohio's 3rd District.

The filing deadline for congressional candidates is Feb. 21.

Hall's district was largely redrawn last month by the Republican-controlled state Legislature to include fewer Democratic voters. Still, Hall was not expected to have trouble keeping the seat, which was considered so safe in 2000 that he was the only Ohio incumbent without a major-party opponent.

Apart from Turner, at least two other Republicans have expressed an interest in the race, including Roy Brown of Brown Publishing Co., whose father and grandfather served in Congress, and David Westbrock, a doctor from Centerville, Ohio.

"Republicans have an excellent chance of electing the next congressman from this area," said Montgomery County GOP Chairman Jeff Jacobson, also a state senator.

Jacobson said Turner would be an "excellent" candidate against anyone, including Hall, but Westbrock and Brown don't live in the district and aren't as well known.

Interested Democrats include Hall's chief of staff, Rick Carne, and Montgomery County Prosecutor Matt Heck.

Hall has long been an outspoken advocate in Congress for hunger issues and human rights conditions. He was chairman of the House Select Committee on Hunger and went on a hunger strike for 22 days in 1993 to protest the abolition of the committee. He later helped found the Congressional Hunger Center and now serves as chairman of the House Democratic Caucus Task Force on Hunger.

In 1994, Hall was among four people nominated by former President Clinton to lead UNICEF. The former Peace Corps worker has been nominated for the Nobel Peace Prize three times since 1998.