JERUSALEM (Reuters) - An Israeli attack on Iranian nuclear sites looks “unavoidable” given the apparent failure of sanctions to deny Tehran technology with bomb-making potential, one of Prime Minister Ehud Olmert’s deputies said on Friday.

“If Iran continues with its program for developing nuclear weapons, we will attack it. The sanctions are ineffective,” Transport Minister Shaul Mofaz told the mass-circulation Yedioth Ahronoth newspaper.

“Attacking Iran, in order to stop its nuclear plans, will be unavoidable,” said the former army chief who has also been defense minister.

It was the most explicit threat yet against Iran from a member of Olmert’s government, which, like the Bush administration, has preferred to hint at force as a last resort should U.N. Security Council sanctions be deemed a dead end.

Iran has defied Western pressure to abandon its uranium enrichment projects, which it says are for peaceful electricity generation rather than bomb-building. The leadership in Tehran has also threatened to retaliate against Israel -- believed to have the Middle East’s only atomic arsenal -- and U.S. targets in the Gulf for any attack on Iran.

Mofaz also said in the interview that Iranian President Mahmoud Ahmadinejad, who has called for Israel to be wiped off the map, “would disappear before Israel does.”

A spokesman for Prime Minister Ehud Olmert did not address Mofaz’s comments directly but said that “all options must remain on the table” and said more could be done to put financial pressure on Tehran.

“Israel believes strongly that while the U.N. sanctions are positive, much more needs to be done to pressure the regime in Tehran to cease its aggressive nuclear program,” spokesman Mark Regev said.

“We believe the international community should be considering further tangible steps such as embargoing refined petroleum headed for Iran, sanctions against Iranian businessmen traveling abroad, tightening the pressure on Iranian financial institutions and other such steps,” he added.

Mofaz’s remarks came as he and several other senior members of Olmert’s Kadima Party prepare for a possible run for top office should a corruption scandal force the Israeli prime minister to step down.

Iranian-born Mofaz has been a main party rival of the Israeli prime minister, particularly following the 2006 elections when Olmert was forced to hand the defense portfolio to Labour, his main coalition partner, at Mofaz’s expense.

Mofaz, who is also designated as a deputy prime minister, has remained privy to Israel’s defense planning. He is a member of Olmert’s security cabinet and leads regular strategic coordination talks with the U.S. State Department.

Israeli planes destroyed Iraq’s nuclear reactor in 1981.

A similar Israeli sortie over Syria last September razed what the U.S. administration said was a nascent nuclear reactor built with North Korean help. Syria denied having any such facility.

Independent analysts have questioned, however, whether Israel’s armed forces can take on Iran alone, as its nuclear sites are numerous, distant and well-fortified.