Iran says any move to bring its nuclear standoff with the West to the U.N. Security Council would mean the end of diplomatic efforts to resolve the issue.
Senior Iranian officials also say the five permanent Security Council members have no legal justification to have Iran referred to the council.
Hours earlier, foreign ministers from Britain, France, Russia, China and the United States - supported by Germany and the European Union - issued a statement saying the International Atomic Energy Agency should vote Thursday to refer Iran to the council.
The statement also said any council action should wait until the IAEA director general, Mohamed elBaradei, delivers a report about Iran's activities in early March.
Iran has previously threatened to break off all cooperation with the U.N. nuclear agency and resume uranium enrichment - the most sensitive phase of the atomic fuel cycle - if the Security Council steps into the dispute.
Some information for this report was provided by AFP and Reuters.