CAIRO � As America talks to�Iran,�Saudi Arabia�is lashing out against it.


The kingdom, Iran�s chief regional rival, is leading airstrikes against an Iranian-backed faction in Yemen; backing a blitz in Idlib, Syria, by jihadists fighting the Iranian-backed Assad regime; and warning Washington not to allow the Iranian-backed militia to capture too much of Iraq during the fight to roll back the Islamic State, according to Arab diplomats familiar with the talks.


Through Egypt, a major beneficiary of Saudi aid, the kingdom is backing plans for a combined Arab military force to combat Iranian influence around the region. With another major aid recipient, Pakistan, Saudi Arabia is also expected to step up its efforts to develop a nuclear bomb, potentially setting off an arms race in the region.


All this comes just a few weeks after the death of King Abdullah and the passing of the throne to�a new ruler, King Salman, who then installed his 34-year-old son Mohamed in the powerful dual roles of defense minister and chief of the royal court.


�Taking matters into our own hands is the name of the game today,� said Jamal Khashoggi, a veteran Saudi journalist and former adviser to the government. �A deal will open up the Saudi appetite and the Turkish appetite for more nuclear programs. But for the time being Saudi Arabia is moving ahead with its operations to pull the carpet out from underneath the Iranians in our region.�


With the approach of a self-imposed Tuesday night deadline for the framework of a nuclear deal between Iran and the Western powers, the talks themselves are already changing the dynamics of regional politics.


The proposed deal would trade relief from economic sanctions on Iran for insurance against the risk that Iran might rapidly develop a nuclear bomb. But many Arab analysts and diplomats say that security against the nuclear risk may come at the cost of worsening ongoing conflicts around the Middle East as Saudi Arabia and its Sunni Muslim allies push back against what they see as efforts by Shiite-led Iran to impose its influence ��often on sectarian battle lines.


Unless Iran pulls back, �you will see more direct Arab responses and you will see a higher level of geopolitical tension in the whole region,� argued Nabil Fahmy, a veteran Egyptian diplomat and former foreign minister.


In Yemen, where a bombing campaign by a Saudi-led coalition killed dozens of civilians in an errant strike on a camp for displaced families, the Saudis accuse Iran of supporting the Houthi movement, which follows a form of Shiite Islam and recently came close to taking control of the country�s four largest cities. (Western diplomats say Iran has provided money to the group but does not control it.) In Bahrain, across a short causeway from Saudi Arabia, the kingdom and its allies accuse Iran of backing opposition from the Shiite majority against the Sunni monarchy.


And Iran has also cultivated clients in government in the great Arab capitals of Damascus, Baghdad and Beirut, the last through its proxy, Hezbollah.


Even if the proposed deal constrains Iran�s nuclear ambitions, the Saudis and their allies note, the pact would do nothing to stop Iran from projecting its influence through such local proxies and conventional arms. Sanctions relief from the deal could even revive the Iranian economy with a flood of new oil revenues.


�The Americans seem nonchalant about this, like, �This is your sectarian problem, you deal with it,��� Mr. Khashoggi said. �So the Saudis went ahead with this Yemen operation.�


Watching Secretary of State John Kerry pursue a deal in Lausanne, Switzerland, many in Saudi Arabia and other Arab states say their ultimate fear is that the talks could lead to a broader d�tente or even alliance between Washington and Tehran.


Washington is already tacitly coordinating with Iran in its fight against ISIS in Iraq. As a result, the American-led military campaign is effectively strengthening the Iranian-backed government in Syria by weakening its most dangerous foe, Arab diplomats and analysts say.


So they wonder what else Mr. Kerry is talking about with his Iranian counterpart, Mohammad Javad Zarif, �on those long walks together� in Lausanne, said Salman Shaikh, director of the�Brookings Doha Center, in Qatar. �Is there something going on underneath the table?�


Easing the hostility between the United States and Iran would tear up what has been a bedrock principle of regional politics since the Iranian revolution and the storming of the American embassy in 1979. �But let�s not forget that we are still dealing with the Islamic Republic of Iran,� Mr. Shaikh said, reflecting the skeptical views of many in the Saudi Arabian camp.


�There is a disbelief in the Arab world that these negotiations are only about the nuclear file, and a frequent complaint here is that we are kept in the dark, we are not consulted,� said Gamal Abdel Gawad Soltan, a political scientist at the American University in Cairo. �The U.S. is much less trusted as an ally, as an insurance policy towards the security threats facing the governments in the region, and so those governments decide to act on their own.�


President Obama has argued that a verifiable deal is the best way to secure the Arab states because it is the most effective way to ensure that Iran does not obtain a nuclear bomb. Even military action to take out Iran�s nuclear facilities, the Obama administration argues, would set it back only temporarily.


By The New York Times