Iranian President Hassan Rouhani pledged Friday that his country would honor what he called a historic agreement to curb its nuclear program, provided that world powers uphold their end of the deal to ease economic pressures.

“We don’t cheat. We are not two-faced,” Rouhani declared in an upbeat televised address to the nation a day after negotiators reached a framework on the nuclear deal. He added: “If we’ve given a promise . . . we will take action based on that promise. Of course, that depends on the other side taking action on their promises, too.”

But a range of other views across the Middle East — including cautious hope in Saudi Arabia, internal dissent in Iran and open hostility in Israel — underscored the potentially difficult diplomatic and security challenges facing Washington among even some of its strongest allies, and how the region’s political dimensions could be reordered by the possibility that the United States and Iran might move beyond an estrangement that reaches back more than 35 years.

In Israel, Prime Minister Benjamin Netanyahu stood firm on his opposition to any deal that allowed Iran the ability to enrich uranium and keep other nuclear technology, saying the deal “would threaten the survival of Israel” and pave the way to an Iranian nuclear bomb.

The framework, Netanyahu said, “would legitimize Iran’s nuclear program, bolster Iran’s economy, and increase Iran’s aggression and terror throughout the Middle East and beyond.”

Highlights of the Iran deal

Saudi Arabia’s King Salman staked out less confrontational ground, telling President Obama that he hoped it would strengthen “stability and security” in the region.

The remarks by Salman suggested no major policy shifts by Saudi Arabia or its Persian Gulf Arab partners after the announcement Thursday of a framework that would place limits on Iran’s nuclear program — but allow some level of uranium enrichment — in exchange for easing international sanctions.

But Salman’s statement, reported Friday by the official Saudi Press Agency, also stopped short of full endorsement, emphasizing the unease in the Gulf and wider Middle East about any steps perceived as benefiting Iran.

Rouhani, speaking from Tehran, told Iranians that the six major world powers negotiating with Iran have now accepted that the nation can enrich uranium on its own soil — a step they had strongly opposed as a nuclear proliferation risk, but that Iran steadfastly contended was a right granted to it as a signatory of the Non-Proliferation Treaty, the pact that governs the spread of nuclear technology.

Iran insists it only wants to produce nuclear fuel for energy-producing reactors and medical applications. Israel and others worry that Iran could one day use the same enrichment process to make warhead-grade material.

“Today is a day that will remain in the historic memory of the Iranian nation,” Rouhani said.

“Some think that we must either fight the world or surrender to world powers,” he said. “We say it is neither of those; there is a third way. We can have cooperation with the world.”

Foreign Minister Mohammad Javad Zarif, who negotiated the framework, and his team were greeted as returning heroes Friday by several dozen well-wishers lining the road from Tehran’s Mehrabad International Airport, built during the time of the Western-allied shah. “Viva Zarif! Viva Araghchi!” the crowd chanted in reference to another of the main negotiators, Abbas Araghchi.

In other parts of Tehran, people shouted from car windows and honked horns in scenes of public jubilation not witnessed since the election of the reform-minded Rouhani in 2013.

But internal fissures also appeared. The framework was slammed by some hard-liners who view it as demanding too many concessions from Tehran.

Hossein Shariatmadari, editor of the hard-line Kayhan daily, was quoted by the Fars News Agency as complaining that Iran exchanged its “ready-to-race horse” for one with a “broken bridle.”

But any backlash in Iran is unlikely to force any scuttling of the deal, which needed the backing of Iran’s supreme leader, Ayatollah Ali Khamenei, to move forward.

Saudi Arabia and the other Sunni Muslim states in the gulf view Shiite-led Iran as their main regional rival. Tensions have further escalated as a Saudi-led coalition carries out airstrikes in Yemen aimed at weakening a Shiite rebel force, which gulf leaders say receives support from Tehran.

In a sign of the White House outreach to the gulf, Obama invited leaders from the six-nation Gulf Cooperation Council — the region’s main political bloc — to an upcoming summit at Camp David. Obama said the gathering will discuss ways to “further strengthen our security cooperation.”

The United States has a host of important military outposts in the gulf, including air bases and the U.S. Navy’s 5th Fleet in Bahrain.

The backing expressed Friday by Salman for the Iran deal — even if tepid — is critical for Washington. Saudi Arabia generally sets the tone for the Arab gulf states. The United States also has faced criticism that allowing Iran to keep the ability to make nuclear fuel could touch off demands for similar technology in the Middle East and open a potential atomic arms race.

“The gulf states, particularly Saudi Arabia, fear the nuclear deal between the United States and Iran is premised on a recognition of rising Persian power in the gulf and the region,” said Fawaz A. Gerges, professor of Middle Eastern politics at the London School of Economics.

But many analysts say they do not believe Saudi Arabia or other gulf states would pursue nuclear arms as a hedge that Iran could one day break the agreement and produce warheads.

“So they are very anxious, very alarmed, but I doubt very much whether Saudi Arabia or the United Arab Emirates would go nuclear,” said Gerges. “It would be a costly and risky option.”

Salman, meanwhile, also must try to calm worries among some members of Saudi Arabia’s ruling elite who may endorse a stronger response from the kingdom.

Last month, a senior Saudi adviser, Prince Turki al-Faisal, said the terms granted Iran — such as allowing some level of uranium enrichment — would be sought by Saudi Arabia and other countries. A week earlier, Secretary of State John F. Kerry visited Riyadh to try to reassure the kingdom’s leaders that the nuclear talks with Iran did not signal a rollback in U.S. security commitments to the gulf.

Meir Javedanfar, an Iranian-born regional affairs lecturer at the Interdisciplinary Center in Herzliya, Israel, an academic and research center, predicted a sharp increase in defense spending by the gulf states despite being hit by a sharp drop in oil prices.

“More important than that, they are very likely to challenge Iran’s influence in the region, in places such as Iraq, Yemen, Syria with even more vigor than before, and in a unified manner,” he said.

The stronger military posture has already been on display in Yemen, where the Saudi-led air campaign began last week, seeking to drive back rebels and allow the return of President Abed Rabbo Mansour Hadi.

William Branigin in Washington and Hugh Naylor in Beirut contributed to this report.

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