Selena Gomez has posted a very busty Instagram snap amid rumours that her on-off boyfriend Justin Bieber is romancing model Yovanna Ventura.

The Come & Get It singer sparked a frenzy among her fans with the snap, which shows her posing with some pals in New York, wearing a dangerously low lace bra-top.

The fire was then fuelled with more speculation after the 21-year old beauty was seen going braless in NYC, showing off a much curvier physique than normal.

Sources have previously told HollywoodLife.com that Gomez was looking into getting her assets enhanced to impress Bieber, claiming the star felt she "(needed) to be the hottest girl in the world to keep his attention".

Either way, one things for sure, Selena - you look amazing!