The British prime minister included the prize as part of the Conservative party's annual Black and White Party to raise money for election campaigns, according to The Sun.
A wealthy Tory supporter has reportedly paid over £10,000 ($15,638) for backstage access to Bieber for four teenage girls.
However, the 18-year-old was allegedly unaware of the auction prize, and may refuse to comply. If so, the party would have to return the £10,000.
Universal Music UK reportedly donated a meeting with Bieber at his concert at London's O2 Arena on March 7.
A catalogue advertising the lot described it as "every girl's dream".
It added: "The four golden ticket holders will get the chance to go backstage to meet face-to-face with the gorgeous teen heartthrob".
A Universal Music UK spokeswoman said the Canadian "wouldn't expect to be informed" about who got special passes to meet him backstage.
Bieber's entourage was recently alleged to have used threatening behaviour against a man in Los Angeles.
He is also rumoured to have rekindled his relationship with ex-girlfriend Selena Gomez.
Watch Justin Bieber's music video for 'Beauty and a Beat' below:
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