The "unplanned" meeting took place at the margins of a European Union summit in Athens, and focused on Iraq, the Middle East and EU issues, Blair's spokesman said.

"By chance he (Blair) had a 25-minute meeting with Chirac. It was very friendly, very useful," the spokesman told reporters.

"They were each in the conference building. The prime minister went to get some fresh air. Chirac had the same idea. It was completely spontaneous and unplanned.

"They discussed Iraq, the Middle East and European issues. It was a wide range of topics."

Blair has been US President George W. Bush's staunchest supporter in the Iraq war, while Chirac led fierce opposition to the conflict. But both leaders agree that the United Nations should play a major role in post-war Iraq.

A French diplomat said that French Prime Minister Jean-Pierre Raffarin joined in the Blair-Chirac discussion, and that the president had insisted the UN must play a "vital" role which should be defined "issue by issue".

Chirac said that with such an approach, France and Britain could reach agreement, the source said. Chirac also hoped that "the unity of the international community can be regained".

Blair earlier said the United Nations should be involved in rebuilding post-war Iraq and not just in providing humanitarian relief.

"We are agreed on the importance of the United Nations in post-conflict Iraq," Blair told reporters after meeting UN Secretary-General Kofi Annan on the sidelines of the EU summit, the first since the fall of Saddam Hussein's regime.

But the Blair spokesman said Britain believed it was too early for a new UN resolution on the future of Iraq. A number of countries, including Germany, have demanded a new mandate by the world body on Iraq.

British Foreign Minister Jack Straw meanwhile held a "good meeting" over breakfast with his counterparts from France, Germany and Spain, Straw's spokesman said.

The four would be joined by their Russian and Bulgarian opposite numbers in the evening and would also hold a meeting with Annan.

Asked if the ministers were planning to issue a statement on the role of the UN in Iraq, the spokesman said: "We want to build a consensus about the right approach. After that we will start doing text."

Asked whether there was friction between Straw and his French opposite number, Dominique de Villepin, the spokesman said: "Everyone taking part in this appears to be doing so in the spirit that we had disagreements... but now all want to work together on how we help the people of Iraq rebuild their country and we want the UN to have a vital role in it."

SPACE.WIRE