"I am very happy that Marcus Hellwig and Jens Koch are finally able to return to us in Germany as free people," Chancellor Angela Merkel told the Bild am Sonntag newspaper, the newspaper for which the two men work.

Koch's father, Andreas Hartmann, said he was overjoyed by the end of the reporters' imprisonment, which had strained relations between Berlin and Tehran.

"I think I did not say anything on the telephone, I just listened and cried uncontrollably," he said in remarks also printed in Bild.

Foreign Minister Guido Westerwelle travelled to Iran personally to retrieve the journalists, in the first trip of the top German diplomat to the country since Joschka Fischer visited in October 2003.

During his brief stay, Westerwelle met with his counterpart