Updated

Israeli Defense Minister Ehud Barak said Tuesday his country has never promised the United States it would hold off from attacking Iran while nuclear talks were taking place.

The comments, in which Barak said that a diplomatic push to reach a compromise with Iran was a waste of "precious time," further exposed a rift between Israel and the U.S. over how to deal with Iran and its nuclear program.

"We are not committing to anything," Barak told Israel's Army Radio. "The dialogue with the Americans is both direct and open."

Israel, arguing that a nuclear Iran would pose an existential threat, has said it will not allow Tehran to acquire a nuclear weapon. It cites Iranian calls for Israel's destruction, Iran's support for Arab militant groups and its development of missiles capable of striking the Jewish state.

Fearing that Iran is moving quickly toward nuclear capability, Israel has repeatedly hinted at an attack if Iran's uranium enrichment program continues to advance. Enrichment is a key process in developing weapons, and Israel says Iran is closely approaching a point where it can no longer be stopped.

The U.S. favors diplomacy and economic sanctions and has said military action on Iran's nuclear facilities should only be a last resort if all else fails.

Officials from the United States, Russia, China, Britain, France and Germany met with Iran in Istanbul last weekend to discuss the country's nuclear program. The talks were described as positive, and they agreed to meet again on May 23 in Baghdad.

Barak told Israel's Army Radio he did not believe the talks would prevent Iran from developing a nuclear weapon. "We regret the time being lost. This is precious time," he said.

Barak said the talks needed to yield quick results.

"It requires a few direct meetings where all the demands are put on the table. There you can see if the other side is playing for time, drawing it out through the year, or if indeed the other side is genuinely striving to find a solution," he said. "In this light, any 'time-outs,' especially when they are this long, do not serve our interests," he said.

"Unfortunately, we maintain the view that this will probably not have an impact or bring the Iranians to cease their nuclear program. Of course we will be happy to be proven wrong," he added.

Earlier this week, Israeli Prime Minister Benjamin Netanyahu said Iran got a "freebie" from the international community, saying the May meeting gave the Iranians an additional five weeks to continue uranium enrichment without any restrictions. He said Iran should be forced to stop this immediately.

Netanyahu was publicly rebuked by President Barack Obama, who said the U.S. had not "given anything away" in the talks.

Iran insists its nuclear program is for peaceful purposes and says it does not seek a bomb. The U.S. and its allies doubt the sincerity of that.

The Obama administration has urgently sought to hold off Israeli military action, which would likely result in the U.S. being pulled into a conflict.