Defense Secretary Ashton B. Carter meets with Saudi Arabia's King Salman, right, in Jiddah. Carter sought to reassure the kingdom of continued U.S. support in the wake of a nuclear deal with Saudi arch-rival Iran. (Carolyn Kaster/Pool via Reuters)

Saudi and U.S. leaders agreed Wednesday to curb Iran’s military reach across the Middle East, amid fears that last week’s nuclear deal with Tehran would encourage it to pursue more aggressive regional ambitions.

Defense Secretary Ashton B. Carter held talks with Saudi Arabia’s king and its defense minister in the seaside city of Jiddah, where Saudi officials have decamped for the Muslim holiday of Eid al-Fitr, as he tours Middle Eastern nations that are anxious about the Iran accord.

As the region’s largest Sunni power, Saudi Arabia has privately issued warnings about the deal, which would curb Shiite Iran’s nuclear program in exchange for the easing of economic sanctions, and those warnings carry weight in Washington. At the end of the Iran nuclear talks, the Saudi government threatened “harsh and determined responses” if Tehran used the proceeds of sanctions relief to enhance support for proxy groups in the region, including Shiite Houthi rebels in Yemen.

But U.S. officials said King Salman voiced solid support for the Iran agreement in his talks with Carter. The monarch noted, however, that the accord must be accompanied by a strong inspections program and measures to put sanctions back in place should Iran violate its terms.

What's next for Iran after the nuclear deal

The talks, the first face-to-face encounter between a top Obama administration official and the Saudi leader since the deal was struck July 14, also addressed the deepening conflict in Yemen. More than 3,000 people have been killed there since a Saudi-led coalition began airstrikes in late March against the Houthis, who Riyadh says receive backing from Iran.

In recent days, forces loyal to Saudi Arabia and embattled Yemeni President Abed Rabbo Mansour Hadi have made major gains against the Houthis, boosting Saudi efforts to reinstall the exiled president.

Carter, speaking to reporters after talks with the Saudi leaders, said he shared their fears about Iran’s influence in Yemen. But he noted that a political solution is crucial.

“The Iranian influence with the Houthis is real,” Carter said, but he insisted that “what Yemen needs is a political settlement that allows peace to be restored.”

Richard LeBaron, a former U.S. ambassador to Kuwait who is a senior fellow at the Atlantic Council, said the military campaign against the Houthis offers Saudi leaders an opportunity to evaluate the post-deal realities in the region.

“It’s a test case of their ability to project power against what they see as an Iranian proxy with direct Iranian involvement . . . especially as, in their view, Iran emerges from the shadows because of the nuclear deal,” he said. “It’s also a test case of U.S. support for Saudi Arabia.”

Washington has sought to reassure friendly Persian Gulf nations that it is a reliable ally despite their misgivings about the Iran deal, which the United States pursued alongside five other world powers. In recent months, the U.S. military has provided intelligence and logistical support to the Saudi campaign in Yemen and has placed personnel at a Saudi operations center where targets are selected.

Iran has finally reached a nuclear deal with the U.S. and international partners. Here's what's in the deal, and what happens next. (Gillian Brockell and Julio C. Negron/The Washington Post)

It also is accelerating weapons shipments and continuing sales of military hardware, including Seahawk maritime helicopters and Patriot missile defense systems.

But whether the Saudi-led coalition will prevent the spread of Iranian influence on the Arabian Peninsula remains unknown.

A Western diplomat, speaking on the condition of anonymity to discuss the conflict, said that Iran and Hezbollah, the Tehran-backed Shiite armed movement in Lebanon, have sent advisers to Yemen. He declined to say how many but noted that even a dozen could have a notable effect by teaching Houthis to operate sophisticated weapons.

Last month, Houthi forces fired a Scud missile into Saudi Arabia. The missile was shot down, but the attack underscored that the group could adopt more sophisticated military technology.

“Over the last four months, the conditions have really allowed Iran to flood the zone,” the diplomat said.

U.S. officials, however, have been hesitant to embrace the Saudi assertion that the Houthis provide Iran with a proxy force that could easily become a permanent military power akin to Hezbollah or Shiite militias in Iraq. “They are essentially Yemeni, and they are part of the spectrum of Yemeni political parties,” the diplomat said.

U.S. officials also hope that Saudi Arabia will prove a strong partner in combating the Islamic State, whose advances have pulled the Obama administration back into Iraq, and other extremist groups such as al-Qaeda in the Arabian Peninsula (AQAP), which has a strong presence in Yemen.

U.S. objectives may diverge from those of Saudi Arabia when it comes to the groups in Yemen, where AQAP has plotted attacks on U.S. soil but Houthi rebels, despite their distaste for the United States, have not.

The diplomat said Saudi Arabia remains “deeply concerned” about al-Qaeda and the Islamic State but prefers to save that fight until the defeat of the Iranian-allied rebels is assured. “They see that the first order of business is restoring a legitimate government” in Yemen, he said.

Read more:

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