Singers Taylor Swift and Justin Bieber are reportedly desperate to collaborate in the studio, but before doing so Swift is keen on getting a permission of her star friend Selena Gomez, who dated the Boyfriend hitmaker for four years.

"First of all, Taylor would never go behind Selena&’s back and work with Justin without first getting her blessing. If Taylor ever collaborated with Justin, it would have to be under extraordinary conditions," said a source, reports mirror.co.uk. 

Meanwhile, Gomez is said to have been taking musical inspiration from Swift.