IRAN stepped back last night from a full-scale international row over its nuclear ambitions and agreed not to restart the most controversial parts of its programme for two months.

Its move, after a tense three-hour meeting with Jack Straw, the Foreign Secretary, and his French and German counterparts, marks a decision by Tehran to cool the dispute after a month of threats that it would reopen nuclear plants that had been sealed by United Nations inspectors. The agreement means that a collapse in talks between Iran and the European Union before the Iranian presidential elections on June 17 is now unlikely. But a clash still looms at the end of July over a deal on what nuclear work Iran might continue.

Mr Straw said yesterday: “These have always been difficult and complex negotiations but they have so far been better than the alternative.” A senior British official added: “We have had difficult moments in the past few years but we have kept the show on the road and we have done so again today.”

Under yesterday’s agreement Iran will keep to the terms of last year’s Paris agreement, at least until the end of July. It will not restart enrichment of uranium, a process that can make nuclear fuel but can also make nuclear weapons. Nor, contrary to recent threats, will it restart conversion of uranium ore to gas at its Esfahan plant.

The talks were held at the Iranian Ambassador’s residence in Geneva, a jumbled fantasy of a château, its Rapunzel-like turrets rising from painted timber and plasterwork, and its rooms decorated with paintings of classical Mediterranean ruins. The eight members of the European delegation faced eight Iranians across a narrow mahogany table. Mr Straw, in the centre, with Joschka Fischer, of Germany, Michel Barnier, of France, and Javier Solana, the EU foreign policy chief, together with their political advisers, sat opposite the turbaned figure of Hassan Rowhani, Iran’s chief nuclear negotiator.

Earlier, over lunch at the French Ambassador’s residence, Mr Straw, M Barnier and Herr Fischer had hammered out their intricate three-way script.

Despite the elegance of that setting — white linen, champagne, and smooth lawns overlooking Lake Geneva — officials said that it was a complicated task to marshal a common front, through translators, in a short time, in the face of much uncertainty about how the Iranians would respond.

Britain, France and Germany, dubbed the EU3, have taken the lead in trying to negotiate a deal with Iran to allay the world’s suspicions that it wants to acquire nuclear weapons. Iran says that its 20-year covert programme, exposed by dissidents three years ago, is intended only to provide fuel for power stations.

It maintains that its work is legal under the Nuclear Non-Proliferation Treaty and that the only offence it has committed is in keeping it secret.

A year ago the United States’s view of the EU3’s efforts was “one of scepticism verging on hostility”, one British official said.

But the US has swung round to backing the three on the condition that if they fail, the EU will join the US in referring Iran’s behaviour to the UN Security Council.

Under yesterday’s agreement Iran will stick to the Paris agreement until the end of July. European countries have promised Tehran that they will put proposals to it by July for the shape of a final agreement “which enables Iran’s civil nuclear programme to go ahead in a way that meets proliferation concerns”.

In effect, Iran has backed down from its threat to break the Paris agreement. Western officials believe that the past month’s tension is triggered by the imminent Iranian elections and hope that, if a moderate leader emerges, it could ease.

Officials said that they gave Iran no commitment about their offer in July, but they will require assurances on how Iran treats reactor fuel, economic and technical co-operation, and “objective guarantees” that Iran is not building weapons.

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