Secretary of State John F. Kerry meets with foreign ministers of the Gulf Cooperation Council in Doha, Qatar. (Brendan Smialowski/Pool photo via AFP/Getty Images)

Persian Gulf Arab states on Monday publicly endorsed the Iran nuclear deal during a visit by Secretary of State John F. Kerry, who said the United States would step up arms sales and intelligence-sharing to counter Iran’s “destabilizing activities” in the region.

“This was the best option among other options — to come up with a solution . . . through dialogue” with Iran, said Qatari Foreign Minister Khalid bin Mohammed al-Attiyah, speaking for the six-member Gulf Cooperation Council, which he heads. “We are confident that all the efforts that have been exerted make this region very secure, very stable.”

The unambiguous backing of the GCC countries could be helpful to the Obama administration as it tries to push the deal, reached in Vienna last month, through a skeptical Congress. Congress has 60 days to review the agreement and is expected to reject it, though not by enough votes to withstand a presidential veto.

The GCC support leaves Israel as the only country in the Middle East to vehemently oppose the agreement, which offers Iran sanctions relief in return for restrictions on its nuclear program. Israel maintains that the Obama administration should have negotiated a better deal, one that would end Iran’s ability to develop nuclear weapons, not merely delay it.

The endorsement by the GCC states — Saudi Arabia, Bahrain, Kuwait, Oman, Qatar and the United Arab Emirates — is a victory for Kerry. Previously, the foreign ministers of those Sunni states had expressed concerns about the deal, fearing that it would give Shiite Iran the means to fund its proxy allies in the region.

But after the meeting with Kerry, Attiyah said at a news conference held jointly with the top U.S. diplomat that the gulf states find provisions of the deal “reassuring to the region.” He said they hope eventually to discuss a total ban on nuclear weapons, “not only in Iran but in all the Middle East.” That was a veiled reference to Israel, the only country in the region thought to possess nuclear weapons, though it has never acknowledged having them.

Kerry said the GCC ministers had agreed that the nuclear agreement “contributes to the region’s long-term security, including by preventing Iran from developing or acquiring a military-nuclear capability.” Iran has repeatedly insisted that its nuclear program is only for non-military purposes, including energy production and medical tests.

The public turnabout on the deal suggests that the GCC countries figure they are better off getting U.S. assistance to counter any rise in Iranian influence. Under the deal, Iran is expected to gain access to an estimated $100 billion frozen in sanctioned accounts, plus future oil revenue.

Kerry came armed with more than reassuring rhetoric. He said the United States would expedite military sales and assistance that President Obama promised in May. It includes more intelligence-sharing, special forces training and exercises, ballistic-missile defense systems, cybersecurity and maritime interdiction of weapons. Kerry also pledged $62 million in humanitarian aid to assist Iraqis displaced by the sectarian violence in their country.

Late Monday in Doha, after Kerry had departed for Singapore, the United States and the GCC issued a joint statement that suggests that the United States would consider using military force if necessary to defend the gulf countries from invasion.

After an assertion that the Iran nuclear deal contributes to regional security, the statement says the United States and the GCC share an interest in keeping the region free from “external aggression.”

“The United States reiterated its commitment to working with the GCC to prevent and deter external threats and aggression,” it says. “In the event of such aggression or the threat of such aggression, the United States stands ready to work with our GCC partners to determine urgently what action may be appropriate, using the means at our collective disposal, including the potential use of military force, for the defense of our GCC partners.”

Kerry’s meeting with the GCC foreign ministers was the latest in a wide-ranging effort to garner support for the deal from Iran’s neighbors. Last month, Saudi Foreign Minister Adel al-Jubeir said Riyadh was reassured by Washington’s assertions that inspections of Iran’s nuclear facilities would be effective and that sanctions would be restored if Iran violates its commitments. Last week, the State Department authorized selling Saudi Arabia $5.4 billion worth of advanced Patriot missiles.

On Saturday, Kerry stopped in Cairo to meet with President Abdel Fatah al-Sissi, and Foreign Minister Sameh Shoukry said Egypt supports the nuclear deal.

The day before Kerry’s arrival, the United States delivered eight F-16s, the first such delivery since military aid to Egypt was resumed in March after being suspended over the government’s crackdown on dissent.

Four of the eight F-16s buzzed the capital shortly after arrival, and Egyptian markings were quickly painted over the U.S. ones.

In Doha, Kerry had a separate meeting with Jubeir and Russian Foreign Minister Sergei Lavrov to discuss the war in Syria. Moscow has backed the government of President Bashar al-Assad. Lavrov told reporters after meeting with Kerry that Russia’s aid to Syria is intended only to counter Islamic State terrorists.

Lavrov also criticized the United States for providing military training to some moderate Syrian rebels, saying it was “counterproductive” in the fight against the Islamic State because the rebels would be focused instead on attacking Syrian government troops.

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