Christmas came early in the UK as a collection of some of the biggest pop stars performed at London's O2 Arena as part of radio station Capital FM's Jingle Bell Ball.<br/> <br />The Saturday show was headlined by Katy Perry and on Sunday, Lady Gaga was the main attraction.<br/> <br />BRITs Critic's Choice nominee Sam Smith took the stage alongside hit makers, Disclosure, whose album hit Number 1 earlier in the year.<br/> <br />The duo says their rapid rise to fame still hasn't sunk in.<br/> <br />SOUNDBITE: Guy and Howard Lawrence, Disclosure, saying (English):<br/> <br />"I don't think it ever will to be honest, it's been such a whirlwind this year, everything that's happened. I think until we stop and have a break we'll kind of look back and go "that was a crazy time," but yeah, when you're in the middle of it you've just got to keep going."<br/> <br />Other artists who entertained the audience included boyband Union J, Jessie J and Jason Derulo.
