Days ahead of much-anticipated talks between Iran and the West, a former Israeli defense official says Iranian nuclear sites will come under attack by Israel if crippling sanctions are not imposed on Tehran by the year's end.

Speaking to Reuters on Wednesday, former Israeli deputy defense minister Ephraim Sneh said the lack of decisiveness by the United States and European Union to adopt tough sanctions against Iran would 'push Israel into a corner' where it would be compelled to attack Iran.

"We cannot live under the shadow of an Iran with nuclear weapons" he told Reuters while on a visit to Britain. "By the end of the year, if there is no agreement on crippling sanctions aimed at this regime, we will have no choice."

"This is the very, very last resort. But ironically it is our best friends and allies who are pushing us into a corner where we would have no option but to do it," Sneh who is also a former member of parliament's defense and intelligence committees explained.

"I wonder if they will do it (a tougher sanctions regime) quickly enough. If not, we are compelled to take action," he warned.

Asked if by action he meant acts of sabotage, Sneh said "a military action" without further elaborating.

Iran faces pressure to halt its nuclear enrichment, as world powers claim its program is aimed at building a nuclear bomb.

Along with world powers, Israel -- the sole possessor of a nuclear warhead in the Middle East -- accuses Iran of efforts to develop a nuclear bomb, maintaining that a "nuclear Iran" is the prime existential threat to its security.

Tehran, however, has denied seeking nuclear weapons and called for the removal of all weapons of mass destruction from across the globe.

The Israeli official's call for tougher sanctions against the Islamic Republic comes while the Tehran government is already under three rounds of UN Security Council sanctions resolutions for its enrichment work.

Sneh also explained that the Israeli-sought sanctions should include a total boycott of the Iranian banking system by the West, a ban on selling Iran refined petroleum products, a ban on selling spare parts to the Iranian energy industry and preventing senior Iranian officials from travelling to Western capitals.

The former Israeli defense official went on to raise doubts about the possibility of Russia and China's consent on fresh sanctions against Iran, saying the involvement of "Russia and China is a myth."

Imposed by the West, such a strategy would be tough enough to work, said the retired Israeli brigadier general.

CS/HGH