Iran's chief delegate to the International Atomic Energy Agency, Sirus Nasseri on Wednesday said such a move would be a step towards "the path of confrontation".
Iran had suspended uranium conversion and enrichment at its plant in the southern city of Isfahan under an agreement reached with EU countries in November, but resumed full operations on Wednesday after rejecting the latest EU offer of economic and political incentives.
Europe and the US have appealed to Iran to reconsider the proposals, while diplomats at the UN nuclear watchdog - the IAEA - are debating Iran's action.
The IAEA board could report Tehran to the UN Security Council, which has the power to impose sanctions.
"I think that would be a grave miscalculation by the US, and particularly by Europe," Nasseri told the BBC.
"There is no legal base whatsoever to go to the Security Council. If it is, it is by political choosing and it will be a big mistake."
The IAEA may pass a resolution
asking Iran to resume suspension
Meanwhile, top nations of the UN nuclear watchdog are expected to call on Iran on Thursday to halt sensitive nuclear work it resumed this week and may stop short of calling on the UN Security Council to take action, diplomats in Vienna said.
Britain, France and Germany, which called an emergency session of International Atomic Energy Agency's (IAEA) 35-member board of governors, submitted a draft resolution to demand Tehran halt atomic work that could be used to develop weapons, the diplomats said.
The draft calls on Tehran to immediately resume "full suspension of all (nuclear) enrichment-related activities including the production of feed material", a European diplomat familiar with the text told Reuters. The diplomat said it did not refer Tehran to the UN Security Council.
While Western countries, Russia and China backed the text, some developing states such as India and Brazil opposed it.
Some developing countries fear the attempt to force Iran to give up sensitive nuclear activities could one day be used against their own nuclear programmes and therefore object to it.
States opposing the text were, however, in a clear minority and the EU's wish to have its text passed outweighed any concern that failing to win unanimous support would undermine the resolution's authority, diplomats said.
One diplomat said the EU did not want to immediately refer Iran's case to the UN Security Council, which has the power to impose sanctions. This was the reason China and Russia supported the European draft resolution, he added.
"I think it is essential that we break this current impasse..."
However, if Iran refused to resume the suspension, the board would probably meet in early September and decide whether to send the matter to the Council, he said.
At the United Nations, Secretary-General Kofi Annan urged Iran and three European Union powers on Wednesday to show restraint and keep talking in hopes of ending their deadlock over Tehran's nuclear ambitions.
"I think it is essential that we break this current impasse, and I believe that the best way to break the impasse is to continue the discussions," Annan said, referring to the long-standing negotiations between Iran and EU members Britain, France and Germany.