European Union officials from Britain, Germany and France met Iran's deputy nuclear negotiator Javad Vaedi today.
The meeting was called by Iran, and diplomats said officials from the three nations were discussing whether talks could resume with Iran over its nuclear enrichment programme.
EU foreign policy chief Javier Solana said the EU would maintain its tough stance against Iran's desire to restart its programme, which the EU and Washington fear could be used to develop nuclear weapons. Iran rejects these claims.
The three EU nations representing the 25-nation bloc, and the United States have called for Iran's referral to the UN Security Council, a move that could lead to sanctions. China and Russia remain unconvinced over a referral.
The Iranians "have taken decisions that were absolutely incompatible with the commitments that they have made," Mr Solana told reporters.
He said he would report back to a meeting of EU foreign ministers over lunch today. He said a possible way out of the crisis is for Iran to sign up to a Russian compromise proposal. Moscow has offered to process uranium on Iran's behalf.
Luxembourg Foreign Minister Jean Asselborn said the EU had to push Iran to accept the Russian proposal. But Iran's top nuclear negotiator, Ali Larijani, said on Friday that the Russian proposal does not meet "all the nuclear energy needs of Iran."
Iranian Foreign Ministry spokesman Hamid Reza Asefi said the door remained open for a compromise between Iran and Europe.
The 35-nation board of the International Atomic Energy Agency meets on Thursday at the UN agency's headquarters in Vienna, Austria, to discuss the Security Council referral.
Uranium enriched to a low level is used as fuel to produce electricity, but further enrichment makes it suitable for use in a nuclear bomb.
AP