The European Union's foreign policy chief and Iran's chief nuclear negotiator on Wednesday abruptly postponed a planned meeting less then a day before they were to hold talks on easing tension over Tehran's refusal to stop enriching uranium.

Cristina Gallach, the spokeswoman for EU top foreign policy official Javier Solana, did not say what prompted the decision to downgrade Thursday's talks in Paris to the level of aides to Solana and Ali Larijani, Iran's senior nuclear negotiator.

But the decision of the two principals to stay away suggested snags needed to be untangled before they considered resuming direct contacts.

The absence of Solana and Larijani was bound to dampen high expectations for the meeting. Two previous rounds that ended in Vienna on Sunday were described by both men as making progress toward solving the impasse over Tehran's refusal to freeze enrichment and the Security Council's demand that it does so.

CountryWatch: Iran

Members of delegations familiar with the outcome of those talks had said that Iran had suggested it was ready to consider suspending the activity for up to two months.

But they also told the AP that Iran continued to refuse pressure to freeze enrichment before talks with a six-nation alliance meant to resolve the nuclear standoff, even though those nations had made such a freeze a condition for the talks to begin.

Gallach said the results of the meeting Thursday would be reported back to Tehran and Brussels before a decision on a new date for a new Solana-Larijani meeting was made.

Gallach, in a telephone call from EU headquarters in Brussels, Belgium, said that the two aides, EU negotiator Robert Cooper and Javad Vaeidi, deputy head of Iran's powerful National Security Council, had already held talks in Vienna on Tuesday.

Different interpretations of what already had been achieved at the earlier EU-Iran talks were reflected earlier in the day in Vienna, with key European nations calling on Iran to negotiate its nuclear dispute with the international community, even as Washington said the time had come to punish Tehran with U.N. sanctions.

In moderate language, the three — Britain, France and Germany — only alluded to the threat of Security Council sanctions if Tehran continues to enrich uranium. The United States, in contrast, said it was now up to the Security Council "to back international diplomacy with sanctions."

The relatively soft tone of the European statement at a meeting of the 35-nation board of the International Atomic Energy Agency appeared focused on keeping confrontation low a day ahead of what then was still thought to be a Solana-Larijani meeting.

Diplomats accredited to the IAEA meeting said that while France and Britain favored a tougher approach, Germany supported a more toned-down text. They asked for anonymity in exchange for sharing confidential information.

Consensus on the text was achieved only after compromise among the three.

The search for agreement — and the sharply different tone of the U.S. and European statements — reflected uncertainties about Iranian intentions after Tehran suggested during talks on Sunday that it was ready to consider a short-term enrichment freeze.

"We continue to extend an open hand to Iran," said the European statement, adding that if Iran met the demand on enrichment, "we will ask to suspend action in the Security Council."

The three said the previous Solana-Larijani meetings "helped clarify some misunderstandings."

"We support these ongoing efforts aimed at convincing Iran to comply with its international obligations, while paving the way for a diplomatic solution," said the statement, delivered by John MacGregor, the chief British delegate to the IAEA.

But U.S. chief delegate Gregory L. Schulte accused Iran of "a history of deception, lack of transparency, provocative behavior and disregard for its international obligations."

"The time has come for the Security Council to back international diplomacy with international sanctions," he declared.

The five permanent members of the Security Council — Britain, France, the U.S., Russia and China — along with Germany, are offering Iran economic and political rewards if it agrees to consider a long-term moratorium on enrichment and commits to an enrichment freeze before talks to discuss details of their package.

Reflecting differences over how to deal with Tehran, they gave up their attempts to join together in criticizing Iran's nuclear defiance on Tuesday after China and Russia refused to endorse U.S.-backed tough language, diplomats said.

Those two countries have resisted U.S.-led efforts to move to sanctions quickly, despite the expiry of an Aug. 31 deadline on Iran to freeze work on developing the technology. Instead, they favor continued negotiations.

The Americans remained tough. U.S. State Department deputy spokesman Tom Casey said Secretary of State Condoleezza Rice will take up the sanctions issue with other diplomats attending the special session of the U.N. General Assembly next week in New York.

And in Vienna, Schulte said of Iran's reported readiness to consider enrichment: "We are interested in more than words. We are interested in action."

Tehran has for more than a year said it would not give up its right to enrichment, which it says it needs to develop to meet future nuclear power needs.

CountryWatch: Iran