Updated

President Bush and British Prime Minister Tony Blair have a lot on their plate Monday as they grapple with rebuilding Iraq and reviving peace efforts in war-torn Northern Ireland and the Middle East.

Bush arrived on the Emerald Isle Monday afternoon EDT. Belfast city airport was closed briefly, after a bomb threat phoned in by someone who didn't realize Bush wasn't landing there.

The president is spending less than a day outside Belfast, meeting with Blair for dinner Monday evening, and then beginning to review progress in the war in Iraq and hammer out the kinks in the plan to rebuild the country and recreate the government when the shooting stops.

The two will announce Tuesday the role the United Nations will play in a postwar Iraq, Secretary of State Colin Powell told reporters. Powell, who accompanied the president, said that the United States and Britain "are not nearly as far apart" as journalists are reporting.

However, he added that the two nations should take a lead in reconstruction of Iraq.

"The coalition, having taken the political risk and having paid the cost in lives, must have a leading role," Powell said.

Powell said that now that "the hostilities phase is coming to a conclusion," it's time to start laying the groundwork for an interim authority. Ret. Lt. Gen. Jay Garner, the head of the Pentagon's reconstruction office, officially opened the Iraq reconstruction office on Monday, and a team of reconstruction specialists are due in Iraq this week.

The reconstruction question is said to have divided not only the United States and Britain -- best friends in Operation Iraqi Freedom -- but also revealed fault lines between Bush's own advisers. Blair wants the United Nations to have a strong hand in a postwar Iraq, whereas Bush wants a transitional authority made up of Iraqi exiles and people living in the country now.

But Powell said that is not the case, and White House spokesman Sean McCormack said the meeting would "further the process of considering these questions about post-Saddam Iraq, reconstruction, humanitarian aid."

Deputy Defense Secretary Paul Wolfowitz gave the impression Sunday that the United Nations would have little to do with a post-Saddam Hussein Iraq. He said a U.S.-led coalition will likely run the country for more than six months until a new Iraqi government is in place.

U.S. officials say Washington and its allies earned the right to call the shots by giving "life and blood" for the country's liberation. They oppose the idea of the U.N. running an interim government in Iraq as in places like Kosovo, East Timor and Afghanistan.

An interim government administered by the United Nations is "not a model we want to follow, of a sort of permanent international administration," Wolfowitz said.

France, Russia and Germany would like the United Nations in charge of a postwar Iraq, but Secretary-General Kofi Annan said he is not set on what role the United Nations will take.

"There have been a series of discussions in Europe, where the European Union has come up firmly, on the side of greater U.N. involvement. I do expect the U.N. to play an important role and the U.N. has had good experience in this area, whether it's the issue of political facilitation leading to the emergence of a new or interim administration," Annan said Monday.

"We've done quite a bit of work on reconstruction, working with donor countries and other U.N. agencies. You've seen the work the U.N. has done on humanitarian rights and the area of human law. So there are lots of areas the U.N. can play a role," he said.

On Monday, British officials glossed over any differences in the American and British approach to a post-Saddam Iraq, and stressed that London and Washington agreed Iraq should eventually be ruled by and for the Iraqis.

"It is absolutely clear we want to see U.N. authority for the operations there in exactly the way we did in operations in Afghanistan," British Defense Secretary Geoff Hoon told a news briefing on Monday.

The Bush-Blair meeting -- which takes place amid tight security -- is the leaders' third face-to-face session in just over three weeks.

They met in the Azores on March 16, along with Spanish Prime Minister Jose Maria Aznar. Bush and Blair also held private talks at the Camp David, Md., presidential retreat on March 27.

Bush's trip to Belfast symbolizes the boldest step of his presidency into the decades-old conflict in Northern Ireland, where a Protestant-Catholic power-sharing agreement broke down last fall.

The agreement came after years of Irish militants battling to wrest the region away from British control.

Former President Clinton made three trips to Northern Ireland, the most of any U.S. president. Clinton's envoy, former Sen. George Mitchell, led the Belfast negotiations that produced the British province's Good Friday peace accord of 1998. That pact sought to end three decades of sectarian conflict in the British territory that saw more than 3,600 killings.

Bush has shown less interest, delegating the business of following Belfast developments to a senior State Department official, Richard Haass.

But a senior administration official said Bush's decision to attend the summit may signal his support for a Blair plan for the region.

Blair will publish his government's new Northern Ireland plans by Thursday, the fifth anniversary of the Good Friday pact.

McCormack said Bush's visit was meant to "lend support" to Blair's efforts.

Bush and Blair even invited Irish Prime Minister Bertie Ahern to lunch Tuesday to join their talks.

Ahern said he supports the British position of giving the United Nations a primary role in the reconstruction of Iraq.

"We want to see a new administration that will have greater legitimacy if it is under the [authority] of the international community," he told reporters in Dublin.

The world leaders will be shielded from mass anti-war protests while at Hillsborough Castle outside Belfast. Still, members of Sinn Fein, the political arm of the Irish Republican Army, planned to demonstrate against the war outside the castle.

Northern Ireland's Social Democratic and Labor Party took a swipe at Bush and Blair and said the two issues of the Iraq war and Northern Ireland peacemaking shouldn't be lumped together.

"I cannot disguise my personal unhappiness at this, given my own opposition to this war and my concern for the integrity of our own peace process," said Mark Durkan, leader of the moderate, mainly Roman Catholic, party.

Bush and Blair also are trying to attract more attention to their peace plan for Israel and the Palestinians. In the past, Blair has held up the progress in Northern Ireland as a model for peace in the Middle East.

White House spokesman Ari Fleischer said there are no plans to release Bush's long-sought "road map" for Middle East peace during the meeting.

The road map, prepared jointly with the European Union, the United Nations and Russia, is designed to reopen negotiations between Israel and the Palestinians once Mahmoud Abbas is confirmed as the Palestinian prime minister.

Those three bodies -- which make up the quartet of Mideast mediators -- have presented Israel and the Palestinians with several drafts. Both sides have made changes, but British and U.S. officials said recently that the final draft would have to be accepted as is.

The White House has said its road map for setting up a Palestinian state by the end of 2005 is not negotiable and that Israel must "play its part" to pave the way.

Abbas and his Cabinet are likely to be sworn in sometime this month.

The Associated Press contributed to this report.