He said he would confront President Putin about Russia's determination to push ahead with the $800m (£500m) deal to build a nuclear power reactor in Iran.

"It is very important for the world to come together to make it very clear to Iran that there will be universal condemnation if they continue with a nuclear weapons programme," he said yesterday.

The Camp David meeting, which ends tonight, comes at a testing time for relations between Russia and the US.

The strong personal relationship Mr Bush used to say existed between the two men has been put under increasing strain by the war in Iraq.

Yesterday Mr Putin joined the long line of world leaders who insist that the UN must play a key role in rebuilding Iraq - a scarcely veiled criticism of America's handling of the issue so far.

Iran is currently under the spotlight for allegedly trying to build up a nuclear arsenal. Earlier this year, International Atomic Energy Agency inspectors found traces of highly enriched uranium at a plant in Natanz, central Iran.

On Thursday experts said they had found minute traces of weapons-grade uranium at a second site. Iran says they were imported on equipment bought abroad.

The UN has set a deadline of October 31 for Iran to prove its claim that its nuclear programme is for energy purposes only. A visit by IAEA officials was postponed yesterday after the Iranians asked for a week's delay to prepare for the inspection.