Israel should launch a pre-emptive strike to prevent arch-foe Iran from going nuclear, a former head of Israel's Mossad intelligence agency said on Monday.

"I am of the opinion that, since there is an ongoing war, since the threat is permanent, since the intention of the enemy in this case is to annihilate you, the right doctrine is one of pre-emption and not of retaliation," Shabtai Shavit told a conference.

Shavit, who served as chief of Israel's foreign spy agency from 1989 to 1996, was speaking at a conference held at the hawkish Bar Ilan University outside Tel Aviv.

"To use retaliation as the main strategy means to sit idly and wait until the enemy comes to attack you," a university statement quoted Shavit as saying.

"But we are dealing with an enemy that plans all the time and waits for the opportunity to arise in order to attack, so what is the point, even morally, to wait and do something only when we are attacked," he said.

Israel, which has the Middle East's sole if undeclared nuclear arsenal, regards Iran as its principal threat after repeated predictions by the Islamic republic's hardline President Mahmoud Ahmadinejad of the Jewish state's demise.

Along with the West, it suspects Iran of trying to develop atomic weapons under the guise of its nuclear programme, a claim Tehran denies.

Israel has backed US-led efforts to prevent Iran developing a nuclear weapons capability through sanctions, but has also refused to rule out military force.

In 1981 Israel bombed an Iraqi nuclear reactor and reportedly also attacked a suspected Syrian nuclear facility in 2007.

Iran insists that its nuclear programme is aimed solely at power generation and medical research and says that the international community should focus its attention on Israel, which, unlike Iran, is not a signatory to the nuclear Non-Proliferation Treaty.

earlier related report
Iran bars two UN nuclear inspectors
Tehran (AFP) June 21, 2010 - Iran said it has barred two UN inspectors from the country over a "false" nuclear report, in a move Washington warned will only deepen world concern about the Islamic republic's atomic programme.

Ali Akbar Salehi, Iran's atomic chief, said the two inspectors had also leaked information about Tehran's atomic work before it was due to be officially announced, ISNA news agency reported on Sunday.

"These two inspectors do not have the right to come to Iran because they leaked information before it was to be officially announced and they also filed a false report," Salehi was quoted as saying.

"In other words because of these two reasons it has led us to (bar) them from coming to Iran," he said, adding Iran has asked the International Atomic Energy Agency (IAEA) to replace the two with new officials, who would be allowed to visit the Islamic republic to check its nuclear facilities.

"In the last session of the IAEA board of governors, we told the IAEA that the report filed by the two inspectors was incorrect and we objected to it," he said.

"The report was totally wrong. Based on the safeguard agreement, we requested that these two inspectors do not come to Iran and be replaced with two others."

Salehi said the decision was also an attempt to convince Iranian lawmakers that Tehran's "cooperation with the IAEA will only be within the framework of the safeguard agreement" between Iran and the UN nuclear body.

The action against the IAEA inspectors comes less than a fortnight after the UN Security Council imposed a fourth set of sanctions on Iran, followed soon after by unilateral punitive measures by the United States and the European Union.

It also comes after the IAEA in its latest report raised fresh doubts about the true nature of Iran's nuclear programme.

The United States voiced concern on Monday about the Iranian decision to block the inspectors' entry.

"It is worrisome that Iran has taken this step, which is symptomatic of its longstanding practice of intimidating inspectors," State Department spokesman Philip Crowley said.

"Reducing cooperation with the IAEA will only deepen the world's concern with respect to its nuclear programme," he added.

Influential Iranian lawmaker Alaeddin Borujerdi, who heads parliament's foreign policy commission, last week called for action against the IAEA inspectors.

"These inspectors provided information to media and Iran's atomic body must stop such violations committed by them," Borujerdi was quoted as saying by state news agency IRNA.

In its latest report on Iran, the IAEA complained Tehran is pressing ahead with its contested uranium enrichment activities -- despite UN sanctions -- and is now producing enriched uranium at even higher levels of purification.

Iran has said it has been enriching uranium to the 20 percent purification level since February, despite the West's belief it does not have the technology to turn that material into fuel rods used to power a reactor.

But on June 16, Salehi said Iran had acquired the technical expertise for making the fuel rods and that the first batch of such fuel plates would be "ready by September next year."

The IAEA report said the agency remained concerned about the true nature of Iran's nuclear ambitions.

"Iran has not provided the necessary cooperation to permit the agency to confirm that all nuclear material in Iran is in peaceful activities," IAEA chief Yukiya Amano told the agency's board of governors this month.

He also described Iran as a "special case" in terms of the agency's monitoring, in view of allegations of possible military dimensions to its contested atomic drive.

Amano said a series of resolutions by the Security Council and the IAEA over the years had made it impossible to treat Iran simply like any other member state.

The West accuses Iran of seeking to build a nuclear bomb, a charge that Tehran vehemently denies.

Iran insists its case should be treated as a routine matter by the IAEA, as with any other member state.

On June 9, the Security Council imposed a fourth set of sanctions on Iran that were followed by US and EU announcements of further unilateral punitive measures.

The broad financial and military restrictions target several Iranian companies, including those linked to the elite Revolutionary Guards.