Rhianna begs Simon Cowell to sign up X Factor's Tamera Foster<>

Rihanna has come out in support of X Factor's Tamera Foster – admitting she has the star quality needed to be a global sensation.

The 25-year-old Diamonds singer says: “I got sent a link of her after she sang one of my songs at Bootcamp and I have been watching her ever since.

"Tamera looks great, she has an amazing voice and she has just the right amount of attitude."

She believes Simon Cowell, 54, will sign up the 16-year-old hopeful – even if she loses the competition. "Simon is a smart guy," she says. "He will know she can sell records all around the world and will sign her to his label."

And Rihanna doesn't think Tamera's controversial past – she has tweeted about drug taking, was caught shoplifting and cautioned by police for attacking another girl – will affect record sales.

"I don't think it matters Tamera has made one or two mistakes in her past," she adds "Show me someone who hasn't and I will show you a liar."

You said it, RiRi!