European Union diplomats say Iran has begun processing small amounts of uranium gas in a further step toward enhancing its nuclear capability.

Unnamed diplomats told reporters Wednesday that Iran's new high-tech centrifuges are designed to enrich uranium by at least twice the rate of previous ones.  Reuters quoted a diplomat as saying the move is a "stunning rejection" of repeated U.N. Security Council demands that Iran suspend sensitive nuclear activity.

The Council has already imposed two sets of sanctions on Iran for its failure to suspend uranium enrichment, a process that can be used to make nuclear weapons.  Officials from Germany and the five permanent members of the Council recently agreed on the text of a resolution that will impose a third round of sanctions against Iran.

Earlier Wednesday Russian Foreign Minister Sergei Lavrov told Russian news agencies that Moscow disapproves of Iran's efforts to enrich uranium and develop rocket technology. 

Lavrov says Iran's activities are not forbidden by international law.  But he said recent years have shown there are a number of problems related to Tehran's disputed nuclear program.

Lavrov warned Iran to refrain from actions that raise tensions and create the impression that Tehran is ignoring the decisions of the international community, the United Nations Security Council, and the IAEA.

Earlier this month, Iran announced it had test-launched a rocket that it said was designed to carry its first homemade research satellite into space.

Washington and its allies accuse Iran of trying to master technology to build nuclear weapons, a charge Tehran denies.

Iran has been building its first nuclear power plant near the southern city of Bushehr.  Officials say Russia has delivered enough nuclear fuel to run that plant, and that the facility will open later this year.

Some information for this report was provided by AFP, AP and Reuters.