Netanyahu, in London to address a conference, said concerted action was required to rein in Iran, not least because of its links with Islamic terrorist groups such as Hezbollah and Hamas. He said he wanted the shipment of Russian nuclear equipment and nuclear fuel to a plant under construction at Bushehr to be stopped.

“The Iranian regime supports terror, both ideologically and operationally,” he said. “I think the regime will go as fast as it can to develop nuclear weapons, regardless of who leads it.”

Netanyahu, prime minister from 1996-9, said that if Iran succeeded in developing nuclear weapons it would boost radical Islamic groups by providing them with “a nuclear umbrella”.

“This is not an Israel problem — this is a world problem that concerns everybody, including Russia,” he said. “There has to be a common solution here: first to prevent the transfer of nuclear technology or fuel, secondly to punish regimes that deviate from this and, thirdly, to put pressure on the Iranian regime, in all avenues possible, to stop this programme.”

Netanyahu contrasted Iran’s apparent determination to develop nuclear weapons with Libya’s decision to abandon its own fledgling programme in response to the American attack on Iraq. “The deterrent effect has worked on some, but so far has not worked on others,” he said.

Asked whether there would ultimately have to be a military solution to the problem — perhaps involving a repetition of Israel’s pre-emptive strike on Iraq’s Osirak nuclear reactor in June 1981 — Netanyahu replied: “I don’t know.” He added: “I am not aware of any plans, but that doesn’t mean they don’t exist, for example in America.”

Netanyahu, who has been critical of the plan by Ariel Sharon, the Israeli prime minister, to withdraw from settlements in Gaza next month, was sceptical that any concessions by Tel Aviv towards the Palestinians would reduce the threat from terrorists.

He said the Palestinian issue was far down the list of grievances cited by Al-Qaeda and other Islamic groups. If Israel were to conclude a peace treaty with the Palestinians, it would be rejected by such Islamic groups, which viewed the Jewish state as a cancer that must be excised.