US President Donald Trump said he was calling off strikes on Iran on Thursday and flagged the signing of a possible deal with Tehran after top-level talks.

"Based on the fact that discussions with the Islamic Republic of Iran have been brought to the highest level of Iranian leadership and approved, I have... cancelled the scheduled strikes and bombings against Iran this evening," Trump said on his Truth Social network.

Trump said “final points” had been approved by all parties involved but gave no further details about what had been agreed.

"Time and place of the signing to be announced shortly," added Trump.

However, he also said that the US naval blockade of Iranian ports, which began in mid-April, would remain in force until the “transaction is finalised.”