"We are exploring among ourselves -- and we are exploring with the Americans -- what the pros and cons (of a new UN resolution) might be," John Sawers said in an interview with London's Financial Times newspaper.

Sawers, who has just ended a three-month stint as Britain's special representative to Iraq, said preliminary negotiations over a new resolution could begin within a few weeks.

But that Britain and the United States would want to know beforehand what role France and Russia -- who both opposed the US-led war -- would insist the United Nations had in Iraq.

"We are all conscious of tensions in the UN Security Council. Before we go down the road of seeking a new UN resolution we would want to be confident it was achievable in a way that would support the coalition's present efforts," he said.

Despite pressure to broaden the international presence in Iraq to share the military and financial burden, the United States has so far been cool to the idea of seeking a new resolution and says existing resolutions provided enough authority for other countries to join post-war reconstruction.

British officials said last month that Britain, Washington's closest partner in the war which ousted Saddam Hussein in April, believed that no new resolution was needed.

The United States however is seeking help to ease the load on the approximately 148,000 US troops in Iraq, which have faced persistent guerrilla attacks since President Bush declared major combat over on May 1.

And it appears reluctant to push any new resolution unless it has some guarantee that others will provide forces.

Russia, France and Germany have indicated that they would send peacekeeping troops or help in other ways if the UN had a bigger role.