Russia's foreign minister, Sergei Lavrov, has warned Western powers they will face "catastrophe" if they attack Iran.
Lavrov said Russia would "do everything" in its power to prevent such an attack, Ria Novosti news agency reported.
"It is impossible to list all the consequences [of an attack]," Sergei Lavrov said in an annual address. "But I have no doubt that it would pour oil on the still smoldering fire of Sunni-Shia confrontation, which would lead to a chain reaction."
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Lavrov also criticized proposed sanctions on Iran's oil industry, saying they had "nothing to do with a desire to strengthen nuclear non-proliferation," but instead sought to hurt the Iranian economy and people "in the apparent hope of provoking discontent."
"As for how likely such a catastrophe is, you need to ask those who constantly mention this as an option," he added.
Lavrov's comments came as Israel assured that no decision had been taken to attack Iran. "This entire thing is very far off," Defense Minister Ehud Barak said today.
According to Haaretz, the head of the American armed forces, General Martin Dempsey, is due to visit Israel this week, prompting speculation that the US would seek to persuade Israel to delay taking action against Iran's nuclear program.
On Monday, the allies agreed to postpone large-scale war games planned for May, apparently because it risked aggravating the situation with Iran.
Meanwhile Iranian Foreign Minister Ali Akbar Salehi indicated today that Iran would participate in international talks on its nuclear activities, at a summit to be held "most probably" in Istanbul, Turkey, reported the BBC.
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