More U.S. combat aircraft are heading home this week as the American military focus in Iraq continues to shift to providing humanitarian relief and postwar security.

A first group of about 10 F-15E attack jets will return to Seymour Johnson Air Force Base, N.C., on Wednesday, and F-15C and F-16Cs are due back at other U.S. bases Thursday and Friday, Air Force officials said. B-2 bombers and F-117A stealth fighters already have returned, and two of the five Navy aircraft carriers that participated in the war left the region last week.

Even before issuing a formal declaration of victory in Iraq, the Bush administration is laying plans for an international donors conference to raise money for Iraq's rebuilding.

Dov Zakheim, the Pentagon's budget chief, said in an Associated Press interview Tuesday that the administration has no current estimate of how many billions of dollars it will take to reconstruct the country, which has been damaged by three wars since 1980 and more than a decade of United Nations sanctions.

Zakheim said a number of countries already are providing or pledging assistance for the earliest stages of stabilizing Iraq and laying a foundation for rebuilding its oil-based economy.

The United Arab Emirates, for example, is contributing a water purification system for Baghdad, and Spain has promised to provide armed peace officers, which he described as constables. Eventually an international constabulary of several thousand officers will be needed, he said.

Saudi Arabia announced Tuesday through its official Saudi Press Agency that it would begin a telethon Saturday to raise money for Iraq. Iran's state-run Tehran Radio said the country's 290 legislators would donate a day's salary to the Iraqi people.

In addition to the estimated $25 billion it has spent on fighting the war so far, the United States has pledged $550 million for reconstruction, and Britain has pledged $330 million, Zakheim said. Australia and Japan have pledged $100 million; Spain, $56 million and Norway and the Netherlands, $21 million each.

Zakheim said France, Germany and Russia - countries that strongly opposed President Bush's decision to invade Iraq - have not yet offered assistance. He would not say whether they would be welcomed as investors in Iraq's future.

Zakheim said he believed there will be more international interest in investing in Iraq's reconstruction than in the case of Afghanistan, which has less appealing prospects for economic revitalization. The initial donors conference on Afghanistan produced pledges of about $2 billion, but the Bush administration complained for months that donors were slow in giving the money.

"There's tremendous interest in getting the Iraqis going because, let's face it, the Afghan economy has been a subsistence economy, whereas Iraq is one of the few Middle Eastern countries that is blessed with both oil and water - in great amounts - which means that it has a naturally balanced economy," he said.

Zakheim said an international donors conference would be held after the World Bank gets a team of experts into Iraq to assess its needs. He said that assessment would take about six weeks.

A spokesman for Zakheim, Lt. Col. Gary Keck, said later that it was not yet clear whether the donors conference would be held under United Nations auspices or through some other organization.