Israeli Prime Minister Benjamin Netanyahu said today he has a duty to prevent Iran from obtaining atomic weapons even when “the best of friends” disagree, referring to policy differences with the United States.

Netanyahu’s comments came after his spoke with President Barack Obama by phone for more than an hour late yesterday as the two nations spar over how to handle the Iran issue. The White House said in a statement that Obama and Netanyahu “reaffirmed that they are united in their determination to prevent Iran from obtaining a nuclear weapon.”

Netanyahu said today that he must prevent Iran from getting nuclear arms “even when it is not easy. Because leadership is tested when it keeps to its goals even when friends disagree and even when they are the best of friends,” he said. His remarks were released in an emailed statement from his office in Jerusalem.

The comments suggest that Netanyahu’s conversation with Obama failed to bridge the gaps between their two governments on Iran or convince the Israeli prime minister that those differences are best aired privately. Israeli leaders have repeatedly said that Iran’s atomic program is for military purposes and presents an existential threat to the Jewish state.

The United States says sanctions against Iran are having an impact and that more talks and international pressure are needed.

‘Moral Right’

Yesterday, Netanyahu said the Obama administration has no “moral right” to keep Israel from attacking as long as the United States doesn’t set its own “red lines” for Iran. His remarks reflect differences over possible military action against the Islamic Republic’s nuclear program and a bid to pressure Obama less than two months before the U.S. election to give Israel more detailed guarantees.

The phone call with Obama came after Israeli media including the Haaretz daily said Netanyahu’s request to meet the president in the United States later this month was snubbed. The White House said no meeting was arranged only because of scheduling issues and that Netanyahu will confer instead with Secretary of State Hillary Clinton.

Former Israeli Prime Minister Tzipi Livni said the dispute between Obama and Netanyahu benefits the Iranians.

“Instead of Iran becoming isolated it is Israel becoming isolated, and the stronger Netanyahu talks, the weaker Israel becomes,” Livni said today in an interview on Army Radio.

Avoiding Uncertainties

Obama’s objective between now and the election is to avoid an Israeli attack “because war introduces uncertainties” that may include a doubling or tripling of oil prices, turmoil in European and American markets and public division over a discretionary war, said Aaron David Miller, a former State Department official who served under Democratic and Republican presidents.

“In a close election you don’t want to alienate anyone,” said Miller, who’s now at the Woodrow Wilson International Center for Scholars, a Washington policy group.

Netanyahu’s criticism probably won’t be a determining factor in the election because Jews aren’t single-issue voters, and most Jewish Democrats have backed Obama, Miller said. Still, he said, “in a close election, of course, anything can happen.”

Obama won in 2008 with 78 percent support from Jewish voters, according to a national exit poll, and he and his supporters have said he has an unbreakable bond with Israel and a record of military and political support to prove it.

Israeli Credibility

Clinton said in an Sept. 9 Bloomberg Radio interview that the United States is “not setting deadlines” on negotiations with Iran. State Department spokeswoman Victoria Nuland later said it is “not useful” to set deadlines or “red lines.”

Netanyahu wants assurances that the United States will commit its own military forces to destroy Iran’s nuclear facilities if economic sanctions and diplomacy don’t succeed, said Miller, who called that aim unrealistic. It “diminishes Israel’s credibility and undermines its deterrent capacity,” he said.

The Israeli leader is also trying to build domestic support in case the government decides to strike, said Emily Landau, director of the arms control and regional security program at the Institute for National Security Studies at Tel Aviv University. He and Defense Minister Ehud Barak “seem increasingly isolated in their support for this option as more and more top security figures come out against it,” she said.

Gabi Ashkenazi, a former Israeli military chief of staff, said yesterday that Israel shouldn’t jeopardize its ties with Washington. Even Barak, one of the most hawkish members of the Israeli security cabinet, yesterday stressed the importance of maintaining Israel’s ties with the United States.

U.S.-Israel Ties

“Despite these differences, and the importance of maintaining Israel’s independence of action, we must also remember the significance of our partnership with America and do everything possible not to harm this,” the Defense Ministry quoted Barak as saying in a private forum.

Dennis Ross, a former senior Middle East adviser to Obama and other U.S. presidents of both political parties who is now at the Washington Institute for Near East Policy, stopped short of ascribing a U.S. political motive to Netanyahu’s remarks.

“If there wasn’t an election right now, I think he’d be saying the same thing,” Ross said.

Ross said Netanyahu is concerned that Israel will lose its own capability to strike if it waits too long. He is trying to “motivate the rest of the world to act more seriously against Iran,” an approach that led to sanctions that otherwise might not be in place, Ross said.

While the disagreements between the United States and Israel should be discussed, “it’s better that they happen behind closed doors,” he said. “What you want is the focus to remain on Iran.”