Christina Aguilera turned down two front row seats for a Britney Spears concert, it was reported today.

The singer, 28, was reportedly offered the chance to see her pop rival in action but refused to accept the offer.

A source said: "Christina thinks that Britney is all style, no substance.

"She thinks the only reason that Britney came back is because people felt very sorry for her."

Britney is currently in the middle of her world tour and recently performed eight shows in London at the O2 Arena.