A top Russian diplomat said a new round of international sanctions on Iran should encourage it to freeze uranium enrichment, a news agency reported Sunday. Deputy Foreign Minister Sergei Kislyak said that a third round of United Nations sanctions on Iran would send a "serious political signal" for Iran to meet the international demands, the Interfax news agency reported. "It contains serious signals for Iran and envisions a certain expansion of the earlier sanctions," Kislyak said of the draft, according to Interfax. "The sanctions are somewhat tightened each time the Security Council passes a resolution. But the tightening is balanced and commensurable with the situation." Last month, the five permanent council members - the United States, Britain, France, Russia and China _ along with Germany agreed on the basic terms of a new UN Security Council resolution that calls for additional sanctions against Iran, including travel bans and freezing assets.