Tehran recently suggested it was ready to discuss a partial suspension of uranium enrichment but the West rejected the overture and Iran has withdrawn its offer to break the nuclear impasse, diplomats said Wednesday

With both sides now back to their hardline positions, talks Thursday between ranking Iranian nuclear negotiator Ali Larijani and Javier Solana, the EU's senior foreign policy representative, are unlikely to make substantial headway, the diplomats told The Associated Press.

Before the talks both Iran and the United States stuck to their guns.

"Suspension is not the right solution for solving Iran's nuclear issue," the Iranian state news agency quoted Larijani as saying before leaving for Spain. Later, on arrival in Madrid, he obliquely blamed the U.S. and its Western allies for their insistence that Tehran fully freeze enrichment, referring to "some mischievous moves by some countries."

U.S. Secretary of State Condoleezza Rice in turn said the world should not soften demands that Iran halt all disputed nuclear work.

"That would be a very big mistake," Rice said of the notion, gaining steam in Europe, that the five permanent Security Council nations plus Germany — the powers in the forefront of trying to engage Iran — should drop their condition that Iran fully suspend enrichment as a precondition to talks starting on a package of incentives.

At their previous talks last month in Ankara, Turkey, both Larijani and Solana spoke of progress and agreed to meet again to try to bridge the divide between Iran's insistence that it has the right to develop an enrichment program and U.N. Security Council demands that it freeze such activities.

Diplomats familiar with the issue said that at least part of the optimism was based on Iran's apparent readiness to discuss a partial and temporary suspension of its enrichment activities.

Iran was ready to stop some — but not all — of its centrifuge machines, which can enrich uranium both to the low level used to generate power and to high-grade material used in the fissile core of nuclear warheads, said one of the diplomats, who demanded anonymity for revealing confidential information. But continued insistence from the U.S. and key Security Council allies Britain and France that Tehran fully suspend its program doomed the chances of agreement.

"It was clear that those on the Western side did not accept any centrifuges (running) at all," said the diplomat. "As a result, the Iranians have gone completely hardline."

Diplomats said evidence of that surfaced at a meeting Friday in Brussels between Larijani's deputy, Javed Vaidi, and senior civil servants of Britain, France and Germany who report directly to their foreign ministers. Also present was a senior Solana aide.

"It was a disaster," said one of the diplomats, saying the two sides parted with no signs of progress on the issue.

Although Iran insists it has the right to the technology to generate nuclear power, it has been hit with two sets of U.N. sanctions because of suspicions bred by nearly two decades of Tehran's clandestine nuclear activities, including questionable black-market acquisitions of equipment and blueprints that appear linked to weapons plans.

Iran's ultimate stated goal is running 54,000 centrifuges to churn out enriched uranium. That would be enough for dozens of nuclear warheads a year.

The issue gained in importance last week, when ElBaradei sent a report to the Security Council that says Iran has expanded its enrichment activities instead of freezing them — a finding that could act as a trigger for a third set of sanctions.

Diplomats and European and U.S. officials suggested Iran had been hoping the international community would accept a compromise based on a Swiss proposal. Under that confidential plan, shared with the AP, both Tehran and the Security Council would have accepted a "double time out" — no expanded work on enrichment in exchange for a pledge to desist from new U.N. sanctions in parallel with attempts to resume formal talks on the nuclear standoff.

On Wednesday, however, a European official described the so-called "Swiss Plan" as "run aground," while a U.S. official said the proposal was "not very active."

A strong U.S. naval presence in the Gulf and Tehran's decision to charge three Iranian-Americans with endangering national security and espionage have not helped ease tensions.

Still, both the U.S. and the European officials expressed the hope that the Madrid meeting would benefit from the positive atmosphere generated by Monday's Iran-U.S. talks — despite that meeting's tight focus on Iraq.

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