Washington (AFP) - US President Donald Trump said Friday that he has written to Iran, pressing for talks on preventing the development of nuclear weapons and warning it faces possible military action if not.

Iran’s foreign minister told AFP on Friday that the country would not negotiate so long as the United States applies “maximum pressure,” but he was not responding directly to Trump’s letter.

Tehran’s mission to the United Nations told AFP that “we have not received such a letter so far.” It was unclear by what means Trump’s missive was transmitted to Tehran.

Trump’s outreach marks a departure at least in tone from the hardline stance that marked his first term and could cause a rift with close ally Israel, which last year carried out bombing strikes inside Iran.

Trump said he wrote a letter to Iran’s Supreme Leader Ayatollah Ali Khamenei telling him that a negotiated solution “will be a lot better for Iran.”

“I’ve written them a letter, saying I hope you’re going to negotiate because if we have to go in militarily it’s going to be a terrible thing for them,” Trump told Fox Business in a clip broadcast Friday.

“You can’t let them have a nuclear weapon.”

A landmark 2015 deal negotiated under former president Barack Obama – known as the Joint Comprehensive Plan of Action (JCPOA) – imposed curbs on Iran’s nuclear program in return for sanctions relief.

It fell apart after Trump withdrew the United States from the agreement in 2018 in his first presidential term and reimposed sweeping sanctions.

Tehran adhered to the deal until a year after Washington pulled out, but then began rolling back its commitments.

Trump, who returned to the White House in January, said he was reinstating his “maximum pressure” policy of sanctions against Iran but that he was doing so only reluctantly.

He has since sidelined officials from his first term associated with his Iran policy, as Trump accuses Washington’s foreign policy establishment of encouraging war.

Trump’s brash billionaire confidant Elon Musk was reported to have met Iran’s ambassador to the United Nations shortly after the election to deliver a message that Trump wants calm and diplomacy.

- Iran warns against US threats -

Iran has been cautious about a return to diplomacy since the collapse of the JCPOA.

“We will not enter any direct negotiations with the US so long as they continue their maximum pressure policy and their threats,” Iranian Foreign Minister Abbas Araghchi told AFP on Friday.

Speaking on the sidelines of an Organization of Islamic Cooperation meeting in Jeddah, Araghchi also warned that Iran’s nuclear program “cannot be destroyed through military operations.”

“This is a technology that we have achieved, and the technology is in the brains and cannot be bombed,” he said.

Araghchi was a key negotiator of the JCPOA, brokered by a then reformist government.

But Khamenei, 85, is the ultimate decision-maker in Iran’s clerical system and has pointed to the JCPOA as proof that the United States is not trustworthy.

Trump’s outreach comes as Iran faces challenges not seen since the 1979 Islamic revolution.

Israel devastated Iranian air defenses and has also pounded two militant movements allied with Iran’s clerical state: Hamas, which carried out the unprecedented attack on Israel on October 7, 2023, and also Lebanon’s Hezbollah.

Iran’s main regional ally, Syria’s Bashar al-Assad, fell in December to Sunni Islamist-led fighters.

Iran has consistently denied claims that it is pursuing nuclear weapons.

Last month, United Nations atomic agency chief Rafael Grossi said Iran was enriching uranium at 60 percent – “almost weapon level” – and that the 2015 deal was an “empty shell” that was “no longer fit for purpose.”

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