JUSTIN Bieber will reportedly take a DNA test later this month to prove he did not father a fan's baby, and will then sue his accuser.

Mariah Yeater, 20, has claimed in a lawsuit that Bieber impregnated her in October 2010 during a 30-second sex session backstage after the singer, then 16, performed in Los Angeles.

Bieber, now 17, has denied the allegations, which he called "crazy" in an interview on NBC's Today show last week.

Sources told entertainment website TMZ that the Baby singer, currently in Europe, will take a DNA paternity test to prove he is not the father when he returns to the US in two weeks.

When the tests disprove Yeater's claim, the sources said, Bieber and his team will sue her.

The teenage superstar has reportedly hired crisis management bigwig Matthew Hiltzik of Hiltzik Strategies to help manage the scandal.

Yeater originally told an ex-boyfriend that he - and not Bieber - was the father of her baby, the New York Post reported last week.

Bieber has denied ever meeting Yeater.