A decades-long silence about Israel's possession of nuclear weapons has been broken in an apparent slip of the tongue by the Israeli Prime Minister, Ehud Olmert, during a visit to Europe.

However, his admissions has sparked controversy at home, where one of his ministers urged a return to silence about the country's nuclear capabilities.

"I would suggest that all those who want to talk about the issue, for God's sake and for the sake of Israel's security, stop it," said the Infrastructure Minister Benjamin Ben Eliezer.

Currently visiting Germany, Mr Olmert appeared to admit in an interview on Monday with a German television station that Israel was among the states that possess an atomic bomb.

He said: "Iran openly, explicitly and publicly threatens to wipe Israel off the map.

"Can you say that this is the same level, when they are aspiring to have nuclear weapons, as France, America, Russia and Israel?"

A spokesman later said he did not mean to say that Israel had or aspired to acquire atomic weapons.

Israel has operated a "policy of nuclear ambiguity" in relation to official statement about its weaponry, although the country is widely believed to be the only nuclear power in Middle East.

According to some estimates, it possesses as many as 200 nuclear warheads.

Mr Olmert is on a three-day trip to Germany and Italy where he had been expected to press European nations to take stronger measures against Iran's alleged nuclear weapons project.

Tehran insists that its nuclear programme is designed purely to generate electricity.

The Israeli premier also warned during a weekend interview that he would "rule nothing out" when asked if he could say that his country would not take military action against Iran.

The subject of Israel's nuclear capability was also touched on last week by the next American defence secretary, Robert Gates, who suggested that Israel had atomic weapons.

He told a Senate confirmation committee that Iran might want an atomic bomb because it is "surrounded by powers with nuclear weapons: Pakistan to their east, the Russians to the north, the Israelis to the west and us in the Persian Gulf".