Talks between Iran and six world powers — including the US for the first time — have ended with no clear answer from Tehran on proposed incentives for suspending its nuclear programme.

The six powers — including the five permanent UN Security Council members — are offering to hold off on passing new UN sanctions against the Islamic Republic.

Speaking at a news conference at the conclusion of the talks in Geneva this afternoon, EU foreign policy chief, Javier Solana, said: “We have not got a clear answer ... we didn’t get an answer ’yes’ or ’no’ and we hope that it will be given soon.

“I hope to have an answer to that and other questions in two weeks’ time.”

He said the talks with Iran’s chief negotiator Saeed Jalili, had been substantive and constructive. Iran had an opportunity to get engaged with the international community, he said.

There had been a response from Tehran to the proposals in the form of a letter, but “we have not got a clear answer to the most important issue that we sent in the document called ’The Way Forward’,” Solana said.

Iranian officials ruled out any freeze in uranium enrichment at the start of talks this morning.

“Any kind of suspension or freeze is out of the question,” an Iranian official said, rejecting the main condition set by the United States and other major powers for formal negotiations to end the dispute.

The high-level US participation in the one-day meeting in Geneva, together with Iranian comments playing down the likelihood of an attack by the United States and Israel, had raised hopes of progress and helped ease record oil prices.

But the optimism was tempered by US insistence that despite the presence of its envoy William Burns, real negotiations could not begin until Iran has frozen sensitive nuclear work, a step Tehran has repeatedly rejected.

Iran’s ambassador to Switzerland said Iran would not accept a freeze.“It is not in Iran’s agenda to discuss this issue,” Keyvan Imani told reporters.

“As our supreme leader (Ayatollah Ali Khamenei) clearly said, our path is very clear: We are not going to abandon our rights.”

Khamenei said on Wednesday Iran was ready to negotiate, but showed no sign of backing down on the Islamic Republic’s refusal to halt atomic activities.

The enrichment issue is key because the activity can produce either fuel for nuclear power stations or the material used in the fissile core of warheads. Iran has defied three sets of UN sanctions demanding it cease its programme, saying it has a right to its peaceful uses under the Nuclear Nonproliferation Treaty. But there is growing concern the Islamic Republic might want to build nuclear weapons instead.

Recent Iranian statements suggest Tehran is looking to improve ties with the US, with officials speaking positively of deliberations by the US administration to open an informal diplomatic presence in Tehran after it closed its embassy decades ago.

Although the US says the Geneva talks focus only on the nuclear issue, Iranian Foreign Minister Manouchehr Mottaki said on Friday they could also result in agreements to open a US interest-protection bureau and have direct flights between the two nations.

US interests in Iran are now represented by the Swiss Embassy in Tehran and official contacts between the two countries are extremely rare.

Imani said Tehran had not yet received a proposal from the US on opening a representation but would "study it positively" if it did.

But he downplayed the presence of Burns at the meeting.

"He is (just) a member of the delegation; of the six countries engaging Iran on the nuclear issue," Imani said.

He also denied that the "freeze-for-freeze" formula — a stop to Iranian enrichment growth in exchange for no new UN sanctions — was formally on the agenda of the Geneva talks, saying the two sides were meeting to discuss common points of their diverging plans to ease nuclear tensions.

Still, Burns' decision to attend the Geneva talks shows that Washington may accept "freeze-for-freeze", which is something less than full suspension, at least as a first step.

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