“Friends can disagree,” Defense Secretary Ashton B. Carter said after meeting with Israeli Prime Minister Benjamin Netanyahu, who reiterated his objections to the Iran nuclear deal. (Daneil Bar-On/European Pressphoto Agency)

Israeli Prime Minister Benjamin Netanyahu made an impassioned case against last week’s nuclear deal with Iran in talks with Defense Secretary Ashton B. Carter on Tuesday, signaling that disagreement over President Obama’s signature foreign policy feat could overshadow other aspects of the United States’ closest alliance in the Middle East.

Netanyahu hosted Carter in the first high-level meeting between Israel and the United States since world powers struck the deal to curb Tehran’s nuclear program in exchange for the easing of economic sanctions on Iran.

Even the protocol surrounding the talks at the Israeli leader’s Jerusalem office appeared to reflect the tensions that have characterized U.S.-Israeli ties for months. Before the meeting, Netanyahu broke from custom and decided not to make opening statements welcoming the U.S. defense chief. The United States provides at least $3 billion in annual military aid to Israel.

Carter, speaking hours after the talks, acknowledged the well-known divisions over the Iran accord. “The prime minister made it quite clear that he disagreed with us with respect to the nuclear deal in Iran,” the defense secretary said during a visit to an air base in Jordan, another stop on his Middle East tour. “But friends can disagree.”

Carter is also set this week to visit Saudi Arabia, a Sunni nation that echoes Israeli fears that ending Shiite Iran’s economic isolation will help it build its regional influence.

Speaker of the House John Boehner (R-Ohio) assured reporters that members of Congress would ask Obama administration officials "much tougher questions" about the nuclear deal with Iran than they faced from the United Nations. (John Boehner/YouTube)

A senior U.S. defense official, speaking at the close of the day, said Netanyahu expressed his “clear and blunt views” in discussions lasting more than an hour.

“It was not unexpected, but . . . we were not there to convince him,” the official said, speaking to reporters on the condition of anonymity to discuss the talks. “We were there to have a conversation about the full spectrum of our relationship.”

Officials said Netanyahu restated his objections to the agreement, including his contention that Iran would use more than $100 billion in funds made available through sanctions relief to threaten adversaries, chief among them Israel. The Obama administration, however, maintains that the deal will make the Middle East safer by blocking Iran’s path to a nuclear bomb.

The U.S. defense official suggested that Netanyahu, who has publicly criticized the agreement in stark terms since it was reached on July 14, used similar language in his meeting with Carter. “I think he has great passion,” the official said. “You’ve seen that publicly, and we saw that passion privately.”

Later in the day, Netanyahu resumed his attack against the Iran deal after meeting with visiting Italian Prime Minister Matteo Renzi, reiterating his contention that the pact is “a historic mistake” and asserting that it will allow Iran to produce “dozens of nuclear bombs in zero time in a decade or so.”

But in what may be a sign of guarded expectations, given the intensity of U.S.-Israeli disagreement, U.S. officials characterized Carter’s visit and talks with Netanyahu as positive.

They said the two sides discussed ways to jointly contain Iran’s support for proxy groups such as Hezbollah, the armed Shiite movement in Lebanon, and Hamas, the Palestinian Islamist group that controls the Gaza Strip.

Those concerns were symbolized in Carter’s visit Monday to an outpost in northern Israel, where Israeli military leaders briefed U.S. officials on the presence of Iranian-backed Hezbollah militants along Israel’s border with Lebanon.

The U.S. officials said the United States and Israel are also exploring ways to deal with instability in next-door Syria, where more than 230,000 people have been killed in a civil war stemming from an uprising against President Bashar al-Assad that began in 2011.

Israel has tried to keep out of the conflict, but like other neighboring nations, it is worried by Syria’s transformation into a theater for extremist groups, including the brutal Islamic State.

Israel and the United States both say Washington will not provide new military aid to Israel as a type of compensation for the Iran accord. The Israeli leadership has been reluctant to accept a new windfall of U.S. weapons amid fierce disagreement over the deal. But both countries said their decades of close military cooperation will continue.

Also hanging over diplomatic ties is the expectation that Netanyahu and other Israeli officials will lobby hard against the deal as a 60-day U.S. congressional review plays out.

Carter’s visit on Tuesday to the Jordanian air base comes as part of U.S. efforts to combat the Islamic State. U.S. aircraft are flying sorties from the base against the group’s fighters in Syria and Iraq.

At the base — which The Washington Post cannot identify under rules set by officials — Carter met with the unit that had been home to a slain Jordanian pilot, Lt. Muath al-Kaseasbeh. Kaseasbeh was captured late last year and burned alive by the Islamic State this year. Jordan, another U.S. ally, promised to escalate its attacks on the Islamic State after Kaseasbeh’s death.

The U.S. military has a squadron of F-16 jets at the base.

William Booth in Jerusalem contributed to this report.

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