Trump threatens 'dropping bombs' if Iran doesn't 'behave'

US President Donald Trump on Wednesday warned Iran he was ready to resume military action if Tehran did not abide by its obligations. [AFP]

US President Donald Trump on Wednesday warned Iran he was ready to resume military action if Tehran did not abide by its obligations, two days ahead of the signing of an accord to end the war between the foes.

"No it's not final. It's a memorandum of understanding," Trump said at the G7, referring to the agreement expected to be signed in Switzerland on Friday.

"If I don't like it, we will go back to shooting at them," he added alongside Egyptian President Abdel Fattah al-Sisi.

"If they don't behave, we'll go right back to dropping bombs right smack in the middle of their head."

"Because they misbehaved for 47 years," he said, referring to the Islamic Republic, founded in the Islamic Revolution after the ousting of the shah, a US ally, in 1979.

The US-Israeli war against Iran began on February 28 with the killing in airstrikes of Supreme Leader Ayatollah Ali Khamenei and other top officials.

The talks on a final US-Iran settlement to end the conflict are set to begin Friday, immediately after the signing of the accord in Switzerland and continue over a 60-day window to flesh out its details.