Former Mossad chief and national security adviser Ephraim Halevy was quoted by the New York Times on Thursday saying that if he were Iranian he "would be very fearful of the next 12 weeks".
Halevy also told Israel Radio on Thursday that if the Iranians "continue to play their games" in nuclear talks with world powers, they would be underestimating Israel's resolve.
"[The Iranians'] math is off if they think they have open-ended immunity" in these talks, he said.
His remarks came just after U.S. Secretary of Defense Leon Panetta's visit to Israel, and amid circulating speculations of possible Israeli plans to strike Iran over its contentious nuclear program.
Panetta's visit coincided with an executive order by U.S. President Barack Obama to increase sanctions against Iran, targeting foreign banks that help Tehran sell its oil.
Prime Minister Benjamin Netanyahu said earlier this week that Israel had not yet decided whether to strike Iran. After meeting with Panetta, he said Wednesday that U.S. statements of solidarity with Israel and its assurances that military strikes are still an option aren't working to convince Iran that the West is "serious about stopping" the Islamic republic from developing nuclear weapons.
Standing with the U.S. defense secretary, Netanyahu said, "Neither sanctions nor diplomacy have yet had any impact on Irans nuclear weapons program."
"America and Israel have also made clear that all options are on the table. You yourself said a few months ago that when all else fails, America will act. But these declarations have also not yet convinced the Iranians to stop their program," he added.
"However forceful our statements, they have not convinced Iran that we are serious about stopping them. Right now the Iranian regime believes that the international community does not have the will to stop its nuclear program. This must change and it must change quickly, because time to resolve this issue peacefully is running out," the prime minster said.
Defense Minister Ehud Barak also told Panetta that he sees an "extremely low" probability that sanctions will ever compel Iran to give up its nuclear activities.
Panetta, meanwhile, denied reports Tuesday that he was to discuss with Israeli leaders plans for attacking the Islamic Republic: "I think it's the wrong characterization to say we are going to be discussing potential attack plans. What we are discussing are various contingencies and how we would respond," he said.
Asked whether these included military options, he said: "We obviously continue to work on a number of options in that area, but the discussions that I hope to have with Israel are going to be more about what is the threat that we're confronting and to try to share both information and intelligence on that."
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