Iranian President Mahmoud Ahmadinejad
Iranian President Mahmoud AhmadinejadIsrael news photo: Flash 90

Just hours after Iran announced it would be expanding centrifuge operations at the underground Fordo nuclear facility near Qoms, the Islamic Republic continued to threaten the West.

Iranian Foreign Ministry spokesman Ramin Mehmanparast warned the U.S. and its allies on Wednesday evening that “hasty steps will lead to heavy casualties,” Channel 2 News reported.

“The U.S. and its Western allies are unable to carry out any operation against Iran,” Mehmanparast was quoted as having said. “Any irresponsible response will lead to heavy casualties.”

He added that the global hegemony against the Islamic Republic is due to its “influence” on world politics. Referring to the accusations that Tehran was behind the latest wave of terrorist attacks against Israeli targets, Mehmanparast said, “Israel commits acts of terrorism, then blames Tehran to divert public opinion.”

Iran also announced on Wednesday that it activated a new generation of centrifuges at its Natanz nuclear site in order to accelerate its uranium enrichment activities.

The United States, however, downplayed Iran's announcement and said it was “not terribly new and not terribly impressive.”

"We frankly don't see a lot new here. This is not big news. In fact it seems to have been hyped," State Department spokeswoman Victoria Nuland told reporters.