Beyoncé: "I never imagined success"

Beyoncé Knowles has revealed that she was never as ambitious as she is now and could never have imagined her success.

The 'Single Ladies' singer admitted that she originally planned to retire at an early age.

"This is really funny but when I was younger I thought I'd be retired by 30," she told Cosmopolitan. "Now I'm nearly there I can't believe how much more I want to do."

Speaking of her career to date she commented: "I never imagined I'd have as much success as I've had. I thought it would be great just to get a record out.

"I never imagined the extent of what I've achieved. I never imagined the awards, the movies... I still can't believe it. I'm grateful for all of it and don't take it for granted.

"When I do something, I try and do it as well as I can."

Beyoncé is due to headline this year's Glastonbury Festival.

The star recently announced that she has donated money earned from a concert staged for the family of Muammar al-Gaddafi, following protests against the Libyan leader's regime.