JERUSALEM — Israel’s military chief said in an interview published Wednesday that he believes Iran will choose not to build a nuclear bomb, an assessment that contrasted with the gloomier statements of Prime Minister Benjamin Netanyahu and pointed to differences over the Iran issue at the top levels of Israeli leadership.

The comments by Lt. Gen Benny Gantz, who said international sanctions have begun to show results, could relieve pressure on the Obama administration and undercut efforts by Israeli political leaders to urge the United States to get as tough as possible on Iran.

Netanyahu and Defense Minister Ehud Barak have repeatedly stressed that they do not think sanctions and diplomacy will persuade Iran to halt a nuclear program they describe as a military one, and they warn that the time to stop it is quickly shrinking.

But the Israeli security establishment is believed to be far less convinced about the urgency of military action. Gantz made his own reservations clear in a handful of rare interviews with Israeli newspapers, offering comments that analysts said seemed intended to inject nuance into a debate that has reached frenzied heights this spring. Speaking to the newspaper Haaretz, he said that the Israeli military would be ready to act if ordered, but that he did not think that this year would be “necessarily go, no-go.”

Gantz described Iranian leaders as “very rational people” who are still mulling whether to “go the extra mile” and produce nuclear weapons.

“I believe he would be making an enormous mistake, and I don’t think he will want to go the extra mile,” Gantz said of Ayatollah Ali Khamenei, Iran’s supreme leader. While Gantz cautioned that Khamenei could still change his mind, the supreme leader has said repeatedly that Iran does not intend to build a nuclear weapon, and that its uranium enrichment program is for peaceful purposes.

Although striking in its bluntness, Gantz’s assessment of Iran’s nuclear intentions did not differ dramatically from comments made publicly and privately by other current and former Israeli officials in recent months. Others have also concluded, for example, that Iran intends to achieve nuclear weapons capability but would stop short of assembling and testing a bomb, steps that would almost certainly incur a military response from Israel and perhaps the United States.

But Gantz’s comments differed starkly in tone from those made recently by Netanyahu about the diplomatic efforts of the United States and other world powers. The prime minister recently dismissed the five-week break between this month’s nuclear talks in Istanbul and the next round as a “freebie” that awarded Iran more time to work toward making bombs.

“The centrifuges are still spinning,” Netanyahu told CNN this week. “They were spinning before the talks began recently with Iran, they were spinning during the talks, they’re spinning as we speak. So if the sanctions are going to work, they’d better work soon.”

Ray Takeyh, a former State Department senior adviser on the Persian Gulf region, said Gantz’s comments suggest that Israeli officials, like many of their counterparts in Iran and the United States, are looking for ways to step down from the current crisis.

“Netanyahu is skeptical of the negotiations as a means for Iran to drag things out,” said Takeyh, a senior fellow at the Council on Foreign Relations, “but you’re seeing a lot of discussion in the Israeli military suggesting that Israel would like to have a greater degree of flexibility.”

Dennis Ross, who until last fall was the White House’s point man on Iran and the Middle East, said the remarks reflect the fact that “ in the Israeli security establishment there are different views.”

The interviews with Gantz were released as Israel began commemorating its back-to-back Memorial and Independence Days, when Israelis both celebrate the achievement of forging a Jewish state in the Middle East and mourn the sacrifices its citizens have made to stay here. Though talk of an Israeli strike on Iran has cooled in recent weeks, the issue tinged this year’s holiday ceremonies.

Israel views the possibility of a nuclear Iran as an existential threat, and Netanyahu has embraced preventing that scenario as his core mission. When asked whether Iranian leaders are rational — a regular subject of debate here — hawkish Israeli officials argue that murderers who carefully plot their crimes are also rational.

In a speech at a Holocaust Day ceremony last week, Netanyahu said: “The regime in Iran openly calls and determinedly works for our destruction. And it is feverishly working to develop atomic weapons to achieve that goal.”

Netanyahu’s comparisons of the Iranian threat to the Holocaust have been criticized in Israel as unnecessary fear-mongering. Gantz, who is known for his calm demeanor, seemed to echo those calls for restraint.

“Despair not,” he told Haaretz. “The state of Israel is the strongest in the region and will remain so. Decisions can and must be made carefully, out of historic responsibility but without hysteria.”

Shlomo Brom, a retired general who is now an analyst at the Institute for National Security Studies in Tel Aviv, said Gantz’s comments indicated he “doesn’t want to be pushed into rash decisions, so he’s trying to cool it a little bit.”

Military analysts cautioned that Gantz’s comments should not be interpreted as defiance of the political leaders to whom he reports. Instead, they reflect the Israeli intelligence community’s assessment that Iran has not yet decided to make nuclear weapons, as well as the Israeli military’s concern about the potential fallout of an Israeli strike — for Israeli civilians and for the reputation of the military if it does not go well, said Amir Oren, a veteran military analyst for Haaretz.

“Many Israelis get the impression that Netanyahu itches for a fight,” said Oren. “The military does not. The military must weigh the consequences.”

Several former security officials have expressed opposition to the idea of an Israeli strike on Iran. One of the most prominent Israeli officials to break publicly with the Israeli government recently was Meir Dagan, the tough-talking former chief of Israel’s legendary Mossad spy agency.

The opinions of top Israeli officials, too, are far from uniform. Many Israeli leaders are convinced that Iran has resumed warhead work in recent years, though on a much smaller scale than existed prior to 2004, when the U.S. intelligence community believes that Iran was actively working on designing a nuclear warhead. Both countries believe that Iran’s priority now is amassing enough enriched uranium to give its leaders the option to make nuclear weapons.

But in recent interviews, some Israeli officials have said they believe sanctions could deter Iran’s nuclear ambitions, particularly if more countries, including Russia, line up behind them; the Israeli finance minister recently described the Iranian economy as “on the brink of collapse.”

Defense Secretary Leon Panetta, in a January interview on CBS’s “Face the Nation,” said he believed Iran would deliberately halt its work just short of the finish line.

“Are they trying to develop a nuclear weapon? No,” Panetta said. “But they are trying to develop a nuclear capability, and that is what concerns us.”

Some Israeli observers described Gantz’s analysis — that sanctions must be given time, but the military option is on the table — as a less theatrical but not fundamentally different one from Netanyahu’s. The big question is how much is bluff, said Or Heller, a military correspondent for Israel’s Channel 10 news.

Gantz indicated that is part of the strategy.

“The military option is the last chronologically but the first in terms of its credibility,” Gantz told Haaretz. “If it’s not credible it has no meaning. We are preparing for it in a credible manner. That’s my job, as a military man.” Warrick reported from Washington. (© 2010 The Washington Post Company 04/26/12)