Madonna has reportedly ended her friendship with Britney Spears - because the "Toxic" singer has quit the Kabbalah.

The pop superstar - who was responsible for introducing Britney to the mystical Jewish cult - has reportedly demanded the return of the 12th-century Kabbalah book she gave the star as a wedding gift.

Madonna has admitted she only married husband Guy Ritchie to make her "look good."

The pop superstar wed the English film director in December 2000 but now says she tied the knot with him for all the wrong reasons.

Singer Britney Spears has given up on her Kabbalah studies, and told her fans that her religion is her baby.

The star has apparently stopped trying to be the next Madonna, who was the person who first introduced Britney to the faith - which is often described as "Jewish mysticism."

Madonna treated fans to a raucous live performance in California on Sunday night - and even played guitar.

The 'Hung Up' singer warmed up for her forthcoming world tour by playing a blistering set at the Coachella music festival, Madonna took the stage in a pair of velvet bondage-style trousers and even strummed a guitar at one point.

Jade Jagger has revealed her style icons are Missy Elliot, Scarlett Johansson, Madonna and Elizabeth Taylor. The fashion designer, and daughter of Rolling Stones legend Mick, says she gets fashion tips from all four of the stars, because each has their own unique style.

Jade is particularly impressed by rapper Missy Elliot and says her flamboyant tracksuits blow her away. She said: "I'm very influenced by street culture. It's a way of putting your personality out there."

Tickets for Madonna's forthcoming shows at New York's Madison Square Garden sold out in just ten minutes. The singer's "Confessions" world tour, which is named after her number one album "Confessions On A Dancefloor," starts in Los Angeles on May 21 and demand is so far outstripping demand.

The 47-year-old songstress announced 40 shows in 21 venues around the world and has sold out all seven shows at London's Wembley Arena, four concerts in Paris, plus all dates in Miami, Montreal, Chicago and Los Angeles.