Israel's leader has played down what is being seen as an embarrassing slip when he appeared to admit the country had a nuclear arms capability.
On Monday, Prime Minister Ehud Olmert included Israel among a list of nuclear states, undoing a decades-old stance of "ambiguity" on whether it had the bomb.
"Our policy has not changed," Prime Minister Ehud Olmert told reporters during a press conference in Berlin.
Some Israeli politicians and newspapers have called for his resignation.
Nuclear analysts believe Israel has a large stockpile of nuclear warheads, but it refuses to confirm or deny their existence.
Israel has never signed the Nuclear Non-Proliferation Treaty (NPT), designed to prevent the global spread of nuclear arms.
As a result, it is not subject to inspections or the threat of sanctions by the United Nations nuclear watchdog, the IAEA.
The controversial remarks came in a TV interview at the start of Mr Olmert's visit to Germany, in which he was asked about Iran's alleged pursuit of nuclear weapons.
He said Israel did not threaten "any nation with annihilation" while he claimed Iran had openly threatened to wipe Israel off the map.
"Can you say that this is the same level, when they [Iran] are aspiring to have nuclear weapons, as America, France, Israel, Russia?" he said.
A day later, following a meeting with German Chancellor Angela Merkel, Mr Olmert insisted the uproar was unnecessary and there was no need for further explanation.
"Israel will not be the first country to introduce nuclear weapons to the region. That is our policy and it will not change," Mr Olmert said.
The "no-first-introduction" argument has been challenged by critics since the 1986 revelations of former nuclear technician Mordechai Vanunu.
Israeli officials have since insisted it is linked to a commitment not to test nuclear weapons in the Middle East, which it has not done.
Mr Olmert's remarks dominated the Israeli press on Tuesday, with some headlines criticising him for "a nuclear slip of the tongue".
He also came under fire from a number of opposition politicians.
Former Foreign Minister Silvan Shalom, of the opposition Likud party, told Army Radio the remarks caused "great harm" to Israel's efforts to prevent Iran acquiring a nuclear weapon.
Silvan Shalom said Mr Olmert had given tools to Israel's enemies
He said the prime minister "gave tools" to Israel's enemies, who questioned why Iran should not be allowed nuclear weapons if Israel confirmed it had them itself.
Another opposition politician, Yossi Beilin of the Meretz party, questioned Mr Olmert's fitness to lead.
"The prime minister's amazing statement regarding nuclear capability indicates a lack of caution bordering on irresponsibility," he is quoted as saying in Israeli daily Yedioth Ahronoth.
However, Yedioth analyst Ronan Bergman suggested Mr Olmert's apparent hint may have been deliberate and intended to boost Israel's deterrent advantage.
Last week, the new US defence secretary, Robert Gates, used a similar form of words to Mr Olmert during a Senate confirmation hearing.
BBC Middle East editor Jeremy Bowen says for political opponents who want Mr Olmert to resign this was only the latest security gaffe.
After failing to deliver the victory he promised in the conflict with Hezbollah in Lebanon in the summer, Mr Olmert's standing as a military leader is low.
Israeli commentators have predicted that Israel will now come under renewed pressure to allow inspections of its nuclear facilities.