The shadow of Barack Obama hung over Donald Trump at the G7 summit on Tuesday as he bristled at comparisons between his deal to end the US war with Iran and his predecessor’s nuclear pact with Tehran.“That was a road to a nuclear weapon,” Trump said of Obama’s 2015 agreement, which he fiercely criticised for years and scrapped during his first term in office. “Mine is a wall against a nuclear weapon,” he added.Trump’s agreement to end the conflict with Iran may have paved the way for a restoration of shipping traffic through the Strait of Hormuz, easing oil prices and rallying equity markets, but it has left him on the defensive.Critics are asking whether the concessions made by Tehran were worth four months of war, billions of dollars in cost, the depletion of US weapons stocks and friction with allies.They are also pointing out his deal is similar to the Joint Comprehensive Plan of Action (JCPOA), which was agreed under Obama and limited Iran’s nuclear programme in exchange for sanctions relief and has been a bugbear of conservatives for years.Referring to Trump’s claim on social media that his deal is the “complete opposite” of Obama’s, Morton Klein, the president of the far-right and consistently pro-Trump Zionist Organization of America, said: “While we hope that is the case, how will this be achieved? There appears to be no agreement at this time on how or whether to remove Iran’s nuclear stockpiles and decommission its nuclear facilities.”Former US president Barack Obama and former first lady Michelle Obama. Photograph: Pablo Martinez Monsivais-Pool/Getty Images Obama himself has weighed in to say that his pact with Tehran was essentially on the same terms as Trump’s.“It is doubtful that any agreement that arises is going to be significantly different, or a significant improvement from the deal that we had in the first place, and had worked for a long stretch of time before we, the United States, pulled out of it,” Obama said in an ABC interview due to be aired on Wednesday.[ Netanyahu and Israel hindering peace efforts with Iran, says TrumpOpens in new window ]Trump’s relationship with his first-term predecessor has always been bitter. He has called Obama “the most ignorant president in history” and a “disaster”. Ditching the JCPOA was one of the signature foreign-policy achievements of his first term.JD Vance, the vice-president and a top Republican contender to succeed Trump in 2028, has been at pains to point out the differences in the two deals as he has defended Trump’s agreement in a series of television interviews in recent days.“If you go back to the Obama JCPOA, what it did was it took an Iranian nuclear programme that it accelerated. It basically bribed the Iranians to stop that programme,” he told CBS. Now, “the Iranian nuclear programme has been completely destroyed, and what we’re saying is: ‘make the long-term commitment to not rebuild it, and you will get the benefits that come with that’,” Vance said.But Trump has still not released the text of the agreement, which is due to be signed at a ceremony in Switzerland on Friday, unsettling many Republicans in Congress.“A deal of this magnitude deserves thorough review. It is critical that the Senate has the opportunity to examine the details, ask tough questions and ensure America’s interests and those of our allies are protected,” said Joni Ernst, Republican senator from Iowa.Asked by a reporter whether he was confident Iran would give up its nuclear ambitions, John Kennedy, a Louisiana Republican senator, answered: “Unless you were homeschooled by a day drinker, no one’s confident that Iran is going to do anything.”As well as scepticism that his deal is tough enough to curtail Iran’s nuclear ambitions, Trump is facing criticism from conservatives over potential sanctions relief for Tehran, the possible inclusion of a $300 billion investment fund to be established for the Islamic Republic and constraints on Israel’s actions in Lebanon.The conservative National Review on Monday called on the president to “release the text” of the pact in an editorial and said: “All told, there is the possibility that Trump would return the US to Obama’s failed Iran deal that Trump rightfully tore up in his first term, which would have all the makings of a humiliation after all of the president’s tough talk.”Democrats are already attacking the deal.“While we want it to end, this agreement will be proof positive to the American people of what an absolute dumpster fire this war has been from start to finish,” Chris Murphy, Democratic senator from Connecticut, said on Tuesday.Brian Katulis, a senior fellow at the Middle East Institute, a Washington think-tank, said even when the text was released, it would be like “Swiss cheese”, given the number of gaps that need to be filled, with many of the toughest issues left to be thrashed out by US and Iranian negotiators over the next 60 days.“This deal essentially resets to the status quo ante with some costs paid to Iran just to reopen the Strait of Hormuz, and then it resets the clock on discussions that they have not been able to get to consensus on the nuclear issues and other things,” he said.However, Katulis agreed Obama’s deal was different from Trump’s. The 2015 pact was “a very detailed and very technical agreement” with “implementation mechanisms and oversight”, he said, adding: “this thing sounds like something that was pieced together over WhatsApp messages”. – Copyright The Financial Times Limited 2026[ Trump and Netanyahu really have fallen outOpens in new window ]