Richard Keys has quit as Sky's football anchorman after claiming that "dark forces" were at work in the sexism scandal that had already cost fellow presenter Andy Gray his job.

Keys earlier apologised for making the disparaging remarks about female assistant referee Sian Massey but insisted he was prevented from making his apology public. He described the remarks as "lads mag banter".

Keys said in a statement released by Sky Sports: "I am deeply sorry for my remarks and the offence they have caused; it was wrong and should not have happened. I have thought long and hard and reached the decision that it is time to move on.

"Going forward without Andy would have been almost impossible.

"I am and will remain proud of our work with football at Sky Sports and grateful to the many people who have worked with me. I wish Sky Sports continued success in the future."