'X Factor' judge Sharon Osbourne has slammed fellow mentor Louis Walsh for choosing to save Irish act The Conway Sisters over Maria Lawson in this weekend's live showdown.

Both acts lost out on the public vote on Saturday night and had to rely on the judges' votes to save them. Walsh was left with the casting vote after Sharon Osbourne and Simon Cowell chose to save their own acts.

After deciding to keep The Conway Sisters in the competition, Walsh said: "I judge the show on tonight's performance but I really think that the girls have a lot more to offer."

But fellow judge Osbourne was furious at seeing Maria, who was one of the favourites to win the show, being evicted. She accused Walsh of choosing to save The Conway Sisters because they are Irish.

Osbourne fumed: "I think this is a travesty. Maria is too talented to stop."

"It was the wrong song, she was way out of her comfort zone. It's a huge lesson for us and I take full responsibility for the song choice," Osbourne said.

Cowell also commented: "This is the very first contestant where the public will think that that artist did not deserve to go. She was definitely judged on her song."