The 54-year-old music mogul took to Twitter to appeal to the star to appear as a panellist on the talent show, just days after she declared Simon and fellow judge Louis Walsh have "murdered music" through 'The X Factor'.

He tweeted: "I think sinead o'connor would be a real fun guest judge on X factor. She loves the show and everything I do. Let me know sinead. (sic)"

Last week, Sinead appeared on Irish chat show 'The Late Late Show' to address her ongoing feud with Miley Cyrus, and hit out at Simon, Louis and 'The X Factor'.

She said: "I don't feel sorry for me or for anybody else in the matter, that's not what it's about. The broader issue, I feel sorry for the murder of music. I feel sorry for the murder of rock 'n' roll which has happened because of the industry. Because of Simon Cowell, Louis Walsh and the lot of them [talent show judges] have murdered music.

"They're murderers of music! I stand and say it on behalf of every musician in the world and they will all agree with it. I don't give a s**t if I hurt them ... All the sexualisation of young people, all the worship of bling and money and diamonds and 'Pop Idol' stuff, Simon Cowell - it all amounts to the murder of music."

However, in 2009 Sinead said that she would compete on the 'X Factor' if she was trying to break into the music industry.