NEW DELHI: A member of Iran's nuclear negotiation team said talks between Iran and big Western powers were unlikely to yield results and it doesn't make sense for Tehran to stop enriching uranium to 20 percent fissile purity.

"Personally speaking, I am not optimistic," Mostafa Dolatyar told reporters at the Iranian embassy in New Delhi on Friday.

"They have made certain connections with purely technical issues and something purely political. As far as this is the mentality and this is the approach from 5+1 or whatever else you call it, definitely there is no end for this game.

Britain, France, Germany, United States, Russia and China, a group known as P5+1, are hopeful of setting dates with Iran to continue talks, a spokesman for EU foreign policy chief Catherine Ashton, who oversees contacts with the Islamic Republic on behalf of the six countries, said on Wednesday.

Dolatyar is a career diplomat who heads the Iranian foreign ministry's think tank, the Institute for Political and International Studies, and is a member of the nuclear negotiation team.

The six countries are particularly concerned about Iran enriching uranium to 20 percent fissile purity, an important technological advance that brings it significantly closer to the threshold of weapons-grade material.

Dolatyar said Iran needed the fuel for its research reactor in Tehran and for medical purposes and could not rely on the international community to supply it.

"One year ago we needed it very much, we were ready to pay cash for it but now we now have it. Why should we close our installations and to buy from somewhere else? It is not logical."

However, he did not rule out a change of position.

"You cannot take something as predecided, everything could be subject to negotiation," he said. "It depends on the framework of negotiations and the end game."