Justin Bieber covers The Beatles’ ‘Let It Be’ – watch

Pint-sized pop star massacres The Beatles' classic during a guest appearance on The X factor USA

Justin Bieber has covered The Beatles‘ ‘Let It Be’ – scroll down to watch it.

The pop brat gave the impromptu performance while appearing as a mentor on The X Factor USA. He was brought in to join judge LA Reid at the judges’ houses stage of the competition. It’s the latest attempt from the US talent show to boost ratings – it’s not yet known who fellow judges including Simon Cowell and Britney Spears will bring in.

Last month, (September 29), Bieber hit the headlines after puking on stage in Arizona during the first night (September 29) of his ‘Believe’ world tour. Bieber was performing ‘Out Of Town Girl’ when he abruptly turned away from the audience and began to spew. The singer then legged it off stage as dancers continued to dance around his sick – watch it below.

Brilliantly, his vocals didn’t miss a beat as his backing track continued to bleat out the song as he sought medical help backstage. Re-emerging a short time after, Bieber apologised to his fans and slowed down the gig by playing acoustic track ‘Fall’.