President Bush and British Prime Minister Tony Blair are meeting for the third time in a month to discuss the war in Iraq, but this time their agenda also includes peace initiatives in the Middle East and Northern Ireland.

Bush was flying to Belfast early Monday for a summit meant principally to review war progress and to iron out differences about how Iraq will be rebuilt and governed when hostilities end.

The reconstruction question has divided Bush's advisers and the United States and Britain. Blair is said to want deeper U.N. involvement in postwar Iraq than Bush, who seeks a transitional governing authority consisting of Iraqi exiles and people living in the country now.

A U.S.-led coalition will likely run the country for at least six months until a new Iraqi government is in place, Deputy Defense Secretary Paul Wolfowitz said Sunday.

The Bush-Blair meeting is their 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 held private talks at the Camp David, Md., presidential retreat March 27.

The Belfast meeting will be used to chart progress in the war, assess humanitarian aid efforts and discuss final-stage battle plans.

By agreeing to meet Blair in Belfast, Bush is taking the boldest step of his presidency into the conflict in Northern Ireland, and blending in a set of issues that complicates his 25-hour trip.

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.

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

Blair, a stalwart ally in Bush's war with Iraq, hopes presidential backing will strengthen his hand when he publishes his government's new Northern Ireland plans by Thursday, the fifth anniversary of the Good Friday pact. A senior administration official said Bush's very presence in Northern Ireland was meant to signal Bush's backing for Blair's blueprint.

Bush and Blair drew Irish Prime Minister Bertie Ahern into their talks on Northern Ireland, inviting him to a lunch on Tuesday afternoon.

The location of the summit, Hillsborough Castle outside Belfast, shields Bush and Blair from the kind of mass anti-war protests that have engulfed London and other European cities. Still, members of Sinn Fein, the political arm of the Irish Republican Army, plan to demonstrate against the war outside the castle.

Northern Ireland's Social Democratic and Labor Party criticized the idea of mixing Iraq war planning with Northern Ireland peacemaking.

"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 breathe new life into the peace process between Israel and the Palestinians. Blair has previously held up the recent Northern Ireland experience as a model to inspire peace in the Middle East.

White House spokesman Ari Fleischer said there are no plans to release the so-called "road map" for Middle East peace during the meeting.

The United States, the European Union, the United Nations and Russia -- 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 recently said the final draft would have to be accepted as is.

The United States and Britain have said the guidelines would be unveiled after the new Palestinian prime minister, Mahmoud Abbas, and his Cabinet are sworn in, probably sometime this month.