Rapper Kendrick Lamar has surprised both fans and his record label with an early release of his hotly-anticipated new album "To Pimp a Butterfly."

The album, a follow-up to the rapper's 2012 hit "good kid, m.A.A.d city", was reportedly due out on March 23 via Aftermath/Interscope, but unexpectedly debuted on iTunes overnight according to Billboard.

The "clean" version of the 16-track album dropped first, quickly followed by an "explicit" version.

Commenting on the release of the record, seven days ahead of schedule, Anthony Tiffith, CEO of record company Top Dawg Entertainment which is responsible for Lamar, seemed less than impressed.

Expressing his distaste via Twitter, Tiffith tweeted: "I WOULD LIKE 2 PERSONALLY THANK @Interscope FOR F*CKING UP OUR RELEASE... SOMEBODY GOTS 2 PAY 4 THIS MISTAKE !!!! #TOP".

"To Pimp a Butterfly" is also available for streaming on Spotify.