Russia's foreign minister warned on Monday that any military strike against Iran would be a grave mistake with unpredictable consequences.
Russia, the closest thing Iran has to a big power ally, is deeply opposed to any military action against the Islamic Republic, though Moscow has supported United Nations Security Council sanctions against Iran over its nuclear program.
The UN nuclear watchdog, the IAEA, is expected this week to issue its most detailed report yet on research in Iran seen as geared to developing atomic bombs. But the Security Council is not expected impose stiffer sanctions as a result.
Israeli media have been rife with speculation that Prime Minister Benjamin Netanyahu is working to secure cabinet consensus for an attack on Iranian nuclear installations.
"This would be a very serious mistake fraught with unpredictable consequences," Foreign Minister Sergei Lavrov said when asked about reports that Israel planned a military strike against Iran.
Lavrov said there could be no military resolution to the Iranian nuclear problem and said the conflicts in Iran's neighbors, Iraq and Afghanistan, had led to human suffering and high numbers of casualties.
A raid on Iran's nuclear facilities would be likely to provoke Tehran into hugely disruptive retaliatory measures in the Gulf that would sever shipping routes and disrupt the flow of oil and gas to export markets, political analysts believe.
Iran is already under four rounds of United Nations sanctions due to concerns about its nuclear program, which it says is entirely peaceful.
Washington is pushing for tighter measures after discovering what it says was an Iranian plot to kill the Saudi ambassador to the United States.
Russia has tried to push Tehran to disclose more details about its nuclear work to ease international concerns.
Senior Russian security officials accept that the West has legitimate concerns about the nuclear program though Moscow says there is no clear evidence that Iran is trying to make a nuclear bomb.
Any military strike against Iran would be likely to sour ties between the West and Russia, whose leader, Vladimir Putin, is almost certain to win a presidential election in March.
"There is no military solution to the Iranian nuclear problem as there is no military solution to any other problem in the modern world," said Lavrov, who has served as foreign minister since 2004.
"This is confirmed to us every day when we see how the problems of the conflicts around Iran are being resolved -- whether Iraq or Afghanistan or what is happening in other countries in the region. Military intervention only leads to many times more deaths and human suffering."
Lavrov added that talks between Britain, China, France, Russia, the United States, Germany and Iran should be resumed as soon as possible.