Jay Z and Justin Timberlake collaborate with Taylor Swift

JAY Z and Justin Timberlake have sparked rumours they're collaborating with Taylor Swift.

The rapper and the 'Mirrors' hitmaker, who have teamed up in the recording studio several times in the past, were spotted leaving the 25-year-old star's penthouse in Tribeca, New York City on Monday, creating speculation they're planning to remix her next single.  

Their visit comes just days after the duo helped the 'Blank Space' singer celebrate her birthday at her home over the weekend.  

Other guests at the private bash included Jay Z's wife Beyoncé Knowles, Emma Roberts, Sam Smith, Karlie Kloss, HAIM, Ansel Elgort, Kelly Osbourne, Nick Jonas Chrissy Teigen and Selena Gomez.  

A source recently claimed Jay, 45, wants Taylor to record a duet with Beyoncé, 33.  

The insider said: "Taylor Swift's birthday was not just a fun celebration, it was also a business meeting for her, Jay Z, Beyonce and Justin Timberlake.  

"Name me four other people that are more powerful in the music world right now. Jay Z is obviously aware of this and he is the ultimate businessman.  

"He knows that Taylor is an extreme powerhouse. He has told Taylor his ideas - he wants to do music with her, and he also wants her to do music with Beyoncé."