(JTA) — President Obama defended his pursuit of a diplomatic resolution of the standoff over Iran’s nuclear program and vowed to defend Israel.

In a lengthy interview Saturday with Thomas Friedman of the New York Times, Obama acknowledged that Israel “is right to be concerned about Iran,” noting the regime’s denial of the Holocaust and repeated threats to eliminate the Jewish state.

Still, Obama reiterated his view that a negotiated agreement with the Islamic Republic is the best strategy to prevent the country from acquiring a nuclear weapon while “sending a very clear message to the Iranians and to the entire region that if anybody messes with Israel, America will be there.”

“There is no formula, there is no option, to prevent Iran from getting a nuclear weapon that will be more effective than the diplomatic initiative and framework that we put forward — and that’s demonstrable,” Obama said.

Obama called the opportunity to reach an agreement with Iran a “once-in-a-lifetime opportunity.” Comparing his engagement with Iran to his diplomatic opening with Cuba, Obama asserted that the United States could pursue detente with Tehran without risking its core strategic interests.

“And so for us to say, ‘Let’s try’ — understanding that we’re preserving all our options, that we’re not naïve — but if in fact we can resolve these issues diplomatically, we are more likely to be safe, more likely to be secure, in a better position to protect our allies,” Obama said. “And who knows? Iran may change. If it doesn’t, our deterrence capabilities, our military superiority stays in place .. We’re not relinquishing our capacity to defend ourselves or our allies. In that situation, why wouldn’t we test it?”

Obama spoke at length about Israel’s concerns about Iran, acknowledging that Israel is more vulnerable to Iran than the United States and that Israel is right to be worried about the regime’s expressed desire to destroy the Jewish state and its denial of the Holocaust.

“But what I would say to them is that not only am I absolutely committed to making sure that they maintain their qualitative military edge, and that they can deter any potential future attacks, but what I’m willing to do is to make the kinds of commitments that would give everybody in the neighborhood, including Iran, a clarity that if Israel were to be attacked by any state, that we would stand by them,” Obama said. “And that, I think, should be … sufficient to take advantage of this once-in-a-lifetime opportunity to see whether or not we can at least take the nuclear issue off the table.”