United Kingdom, July 22 -- Jerry O'Connell has apologised to ex-girlfriend Giuliana Rancic for being a "terrible boyfriend."

The 52-year-old actor dated the entertainment reporter from 2003 to 2004 and she memorably revealed in her memoir that he had cheated on her and then ended their relationship over an intercom, and Jerry has admitted he doesn't blame her for being critical of his conduct because he was "the worst".

Speaking on the Let's Talk Off Camera podcast, Jerry noted he and Juliana had "had a lot of fun together", but added: "Now listen, in Giuliana Rancic's defence of this memoir, I was a pretty terrible boyfriend. Hand up, I was not a good boyfriend.

"Let me take this moment to apologise to Giuliana Rancic. I'm not kidding...