Barack Obama delivered his most explicit threat yet that the United States will attack Iran if that is what it takes to prevent the Islamic republic from developing a nuclear bomb.
The US president also warned Israelis that they would only make a bad situation worse if they moved pre-emptively against Iranian nuclear facilities.
The double-barrelled warning, in an interview with The Atlantic magazine, comes before Mr Obama’s high-stakes meeting with Israeli prime minister Benjamin Netanyahu on Monday and a speech tomorrow to the American-Israel Public Affairs Committee, a powerful pro-Israeli lobby.
Mr Obama said an Israeli strike would stir sympathy for Iran in a region where it has few allies. But he made clearer than before that Iran could face attack from the United States.
“I think both the Iranian and the Israeli governments recognise that when the United States says it is unacceptable for Iran to have a nuclear weapon, we mean what we say,” Mr Obama told the magazine. “I don’t bluff.”
He said Iran and Israel both understood that “a military component” was among a mix of many options for dealing with Iran, along with sanctions and diplomacy, making plain a threat to attack that had previously been more subtly implied.
The warning reveals how the threat that Iran could pose to Israel has eclipsed every other issue in the close, but often contentious US relationship with Israel, and raised the political stakes for Mr Obama.
Iran’s disputed nuclear ambitions dwarf the unfinished business of peace with the Palestinians and Mr Obama’s sometimes testy relationship with Mr Netanyahu.
The White House dispute with Israel is about the risks versus the benefits of a military strike in the near term, not whether one is ever appropriate.
The issue is infused with domestic politics in both the United States and Israel, and Mr Obama is at pains to show American Jewish voters that he is not being harder on Israel than on Iran.
“Every single commitment I have made to the state of Israel and its security, I have kept,” he said in the magazine interview. “Why is it that despite me never failing to support Israel on every single problem that they’ve had over the last three years, that there are still questions about that?”
Mr Obama then suggested an election-year answer to his own question, accusing Republicans of trying to fan the doubts and slam a wedge “between Barack Obama and a Jewish-American vote that has historically been very supportive of his candidacy”.
He firmly rejected the notion that the United States might settle for a strategy of letting the Iranians build a nuclear weapon but deterring them from using one.
“You’re talking about the most volatile region in the world,” he said. “It will not be tolerable to a number of states in that region for Iran to have a nuclear weapon and them not to have a nuclear weapon. Iran is known to sponsor terrorist organisations, so the threat of proliferation becomes that much more severe. ”
Israel has been publicly debating whether to launch air strikes on Iran’s known nuclear facilities in the next several months, before Israel judges that Iran’s programme would be too far along to stop.
The Obama administration argues that the time for a strike is further away, and that there remains enough time to persuade Iran’s leaders to back down. Iran insists its nuclear programme is for peaceful purposes.
Israel wants US backing for any military action against Iran but has signalled it would go it alone if need be. Israeli officials have said they have made no decision yet, but the Obama-Netanyahu meeting comes amid a growing sense in Israel and in Washington that a strike is likely.
Israeli officials appear unmoved by the US arguments, and Mr Obama is unlikely to talk Mr Netanyahu out of launching a strike if the Israeli leader decides not to wait.
Both governments manoeuvred yesterday to set the terms for their discussion.
Mr Netanyahu warned the world not to fall into the “trap” of renewed nuclear talks. Speaking in Canada, the hawkish Israeli leader said he not would set down “red lines” for Israeli or US action on Iran – a reference to reports in Israel that the country intended to press the United States to set such demands.
Until now, Mr Obama has said a nuclear Iran is unacceptable but has not spelled out just what the US would do or when. White House press secretary Jay Carney said yesterday that Mr Obama did not intend to tip his hand to Iran about what lines it cannot cross because doing so would not be in US interests.