Pompeo's comments today in Riyadh and then Tel Aviv came as he neared the end of the Middle East leg of his first trip overseas as America's top diplomat.
President Trump, who has called the President Obama-brokered agreement the "worst deal ever", has until May 12 to decide whether to continue waiving sanctions on Iran that were lifted under the 2015 pact.
He has called for concerted global action to punish Iran for its missile programs and other actions that he said destabilize the region.
Netanyahu has also warned that his country will not accept Iran entrenching itself militarily in neighbouring Syria, where Tehran backs President Bashar al-Assad's regime.
Pompeo reiterated his belief that Trump sees the Iran nuclear deal as "very flawed". They said the incident highlighted the importance of the Trump administration's push to counter Iranian supported-aggression in the region.
Israel has cited Iran's hostile rhetoric, support for anti-Israel militant groups and development of long-range missiles.
Pompeo accused Iran of supplying missile technology and weapons to rebels in Yemen.
Netanyahu said "Iran is trying to gobble up one country after the other".
Camera Icon Saudi Forein Minisder Adel al Jubeir said the kingdom supports the Trump administration’s stance against
Although Netanyahu praised the USA recognition of Jerusalem as bold and historic, he met Pompeo in Tel Aviv, not in Jerusalem as originally planned.
The Iran nuclear deal was signed between China, France, Germany, Russia, the United Kingdom and the U.S., as well as the European Union, and saw Iran commit to halting its nuclear programme in exchange for the lifting of economic sanctions. But he said unless substantial changes are made, it is "unlikely" Trump will remain in the deal.
"The nuclear deal or any other subject under its pretext is not negotiable in any way", he told his French counterpart Emmanuel Macron in a phone call, quoted by the presidency website.
Pompeo also said that the relocation of the American embassy to Jerusalem, a move set to take place on May 14, was "recognising (the) reality" of "Jerusalem as the capital of Israel and the seat of its government".
On his first official trip overseas, Pompeo met with Israeli Minister Benjamin Netanyahu to in Tel Aviv on Sunday to discuss both countries' concerns about Iran. The accord provides Iran with sanctions relief in return for curbs on its nuclear program.
He's also urging Saudi Arabia and its neighbors to resolve a long-festering dispute with Qatar that US officials say Iran is exploiting to boost its influence in the region, including in Yemen and Syria.
Asked about Saudi troops on the ground in Syria, Pompeo said: "We will sit down and talk about. how to best make sure that this is not America alone working on this, it's the Gulf states working alongside us".
In Washington, US National Security Adviser John Bolton also said Trump was still considering his options.More news: Unite Students (LON:UTG) Stock Rating Reaffirmed by Liberum Capital
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