Iran's President Masoud Pezeshkian has issued a rare apology to neighbouring countries affected by its recent missile and drone strikes, while insisting it will never surrender to pressure from Israel and the United States.

Iran's enemies "must take their wish for the unconditional surrender of the Iranian people to their graves," Pezeshkian said, in a speech broadcast on state TV.

Israel and the United States launched strikes against Iran on February 28, killing the supreme leader Ali Khamenei and triggering a regional conflict.

Iran has since responded with missile and drone strikes on Israel and US interests in regional countries, mainly in the Gulf.

Pezeshkian is among three members of an interim leadership council that has been in charge of Iran since Khamenei's killing.

During the speech, Pezeshkian apologised to neighbouring countries for Iran's attacks across the region, saying that they would not be targeted unless attacks originated from them.

"I must apologise on my own behalf and on behalf of Iran to the neighbouring countries that were attacked by Iran," he said.

"The interim leadership council agreed yesterday that no more attacks will be made on neighbouring countries and no missiles will be fired unless an attack on Iran originates from those countries."