"Halting uranium enrichment is definitely deleted from the literature of Iran’s nuclear activities," foreign ministry spokesman Mohammad Ali Hosseini told reporters.
"In our negotiations the halting of this activity has not been on the table and going back on time is not envisaged," he added.
A suspension of enrichment — a process that can be used both to make nuclear fuel and atomic weapons — has been the key demand of Western powers and main sticking point for opening negotiations over the nuclear programme.
The comments come ahead of eagerly awaited talks on Wednesday at a location that has yet to be confirmed between Solana and Iran’s top nuclear negotiator Ali Larijani, in a bid to break the deadlock in the nuclear standoff.
The pair, who held several rounds of discussions last year which failed to find a solution to the crisis, last met face-to-face for informal talks on the sidelines of the Munich security conference on February 11.
It remains to be seen what result can come out of the new meeting, given Iran’s insistence that it enriches uranium and the EU position that Tehran must freeze the process before full negotiations can begin.
"Negotiations which start with good intentions will have positive effects and will lead to consequences which are satisfactory for both sides," Hosseini said, without elaborating.
"What is most important in this is to confirm and guarantee Iran’s right to use nuclear technology for peaceful purposes based on international laws," he added.
The UN Security Council has already imposed two sets of sanctions against Iran for refusing to halt sensitive atomic activities and has threatened to take further punitive action if Tehran’s defiance continues.
The United States, which accuses Iran of seeking to make nuclear weapons, has never ruled out the option of military action to bring Tehran to heel. Iran insists its nuclear drive is solely for generating energy.
Iran has shown no sign of yielding, saying that its uranium enrichment operations have reached an industrial level and announcing it wishes to install over 50,000 uranium enriching centrifuges at a plant in Natanz.
Western observers however have said the extent of Iran’s progress remains unclear and diplomats at the UN nuclear watchdog in Vienna have said it has installed only 1,300 centrifuges so far.
The prime minister of Iran’s arch foe Israel, Ehud Olmert, said that Tehran was "far from attaining the technology threshhold and this country is not close to getting it, contrary to statements by its leadership."
Iran’s first nuclear power station is being built with Russian help in the southern city of Bushehr but its completion has been delayed repeatedly and the nuclear fuel promised by Moscow has yet to arrive.
A top Iranian nuclear official, Ahmad Fayaz Bakhsh, is currently in Moscow for talks aimed at clarifying the situation.
"If the Russians do not abide by their commitment regarding the start of the nuclear power station this will bring their credibility into question," said Hosseini.