Sirus Nasiri, a senior Iranian negotiator at the latest round of talks in Paris, said on Wednesday that Iran would not consider terminating uranium enrichment, as demanded by France, Britain and Germany, but that all four parties would meet again soon to continue negotiations.
"There will be a further discussion within the next few weeks," he said, adding that Iran did not want the talks to drag on forever.
"Time is of the essence."
European diplomats, speaking in advance of the talks, had said this would be the best possible outcome - that Iran would agree to continue talking.
Nasiri described Wednesday's talks as "businesslike, rather intensive".
Iran says it is agreeable to
increased IAEA inspections
The meeting was the latest step in a diplomatic initiative that began in October 2003 when Iran first promised to suspend all work linked to the enrichment of uranium, a process of purifying uranium for use as fuel in power plants or bombs.
This initiative collapsed early last year but was revived in December.
After the talks, Nasiri restated Iran's position that giving up enrichment was not an option.
"This is not something we are prepared to consider. However, as you know the Europeans have a view on that," Nasiri said.
Before the talks, a European diplomat said the EU was not in a position to compromise on the question of Iran's enrichment programme, now that the Americans were officially backing them.
"We both have our entrenched positions," the diplomat said. "With the Americans on board, the EU three couldn't move if they wanted to."
Nasiri gave no indication of when or where the next round of EU-Iran talks would take place.
Prior to the meeting, several Iranian officials had threatened to break off negotiations with the Europeans if there was no progress made.
"We both have our entrenched positions. With the Americans on board, the EU three couldn't move if they wanted to"
Nasiri gave no indication that Iran was preparing to end the talks with the Europeans. Nor did he give any hint that Tehran would resume activities linked to enrichment.
Tehran has suspended enrichment as a confidence-building measure but has made it clear that it would eventually resume the programme.
Sharing US suspicions that Tehran may be planning to develop nuclear arms, France, Britain and Germany are offering Iran political and economic incentives to terminate and dismantle its uranium-enrichment programme as an "objective guarantee" that it is not a front to develop an atomic bomb.
Tehran refuses to give up the programme, and has offered to permit increased inspections by the UN's International Atomic Energy Agency (IAEA) and to limit its enrichment to levels far below the high levels of purity needed to fuel an atomic weapon.
The Europeans have rejected this proposal.