Iran made a surprising move on Wednesday by releasing the 15 British sailors 13 days after it detained them for "illegal entry" into Iranian waters which had strained relations between Tehran and London.

British naval personnel who were detained in Iran wave to journalists after they were released as a 'gift to the British people' by Iranian President Mahmoud Ahmadinejad in Tehran April 4, 2007.  (Xinhua/Reuters Photo)

"While we insist on our rights, the 15 sailors have been pardoned and we offer their freedom to the British people," Iranian President Mahmoud Ahmadinejad told a news conference in Tehran, broadcast live on Iranian television.

"After the press conference, they will be sent to the airport to take a flight to their own country," he added.

But Iran's official IRNA news agency later quoted "an informed source" as saying that the freed British naval personnel will leave Tehran on a flight Thursday morning.

Shortly after the press conference, Ahmadinejad participated in a "ceremony" for the 15 British sailors' release in his presidential compound, Iran's state television reported.

The television's footage showed Ahmadinejad was shaking hands with the British naval personnel and talking to them.

(Xinhua)