Trump: Iran deal says 'loud and clear' that Tehran won't have a nuclear weapon

US President Donald Trump maintained on Tuesday that an interim accord with Iran makes clear that Tehran would never be allowed to develop a nuclear weapon, and he also suggested Syria could be better positioned to disarm Hezbollah.

Speaking ahead of talks with Qatar's Emir Sheikh ​Tamim bin ‌Hamad Al Thani on the sidelines of the G7 summit in France, Trump defended the 14-point memorandum of understanding with Iran that has yet to be made public.

"The only thing that really matters to me is Iran will never have a nuclear weapon, and it says it loud and clear," he told reporters.

US and Iranian officials are due in Switzerland on Friday to begin detailed negotiations, opening a 60-day window for complex technical talks. These are expected to cover issues such as the future of Iran's highly enriched uranium and the lifting of sanctions.

European allies have voiced concern that an inexperienced US negotiating team could struggle to secure a robust agreement, potentially leading to a prolonged standoff.

In 2015, former US President Barack Obama secured a nuclear deal with Iran in exchange for sanctions relief, a process that took two years to finalise. Trump withdrew the United States from that accord during his first term. "This deal is a wall to a nuclear weapon. His (Obama) deal was a road to a nuclear weapon. My deal, they can't have a nuclear, they get blown up," Trump said.

One key factor in whether the interim accord holds will be the situation in Lebanon, where Israeli Prime Minister Benjamin Netanyahu ‌has said his troops would remain in the south as long as needed to tackle Hezbollah. Tehran has demanded an Israeli withdrawal.

Trump appeared critical of Israel's strategy in Lebanon and also suggested that neighbouring Syria - which under President Ahmed al-Sharaa is struggling to stabilise the country after years of civil war - could be best placed to intervene. "I suggested to Israel to let Syria take care of Hezbollah because to be honest, I think they do a better job of doing it," he said.