Dave Grohl reunites with Krist Novoselic and Butch Vig

Dave Grohl has been in the studio working with his former Nirvana bass player Krist Novoselic and Nirava's 'Nevermind' producer Butch Vig.

Vig tweeted the news writing, "The last 24 hours have been surreal! Had a great gig at the El Rey last night, and spent today recording with Dave, Krist and special guest!".

The last time Butch, Dave and Krist worked together was on the iconic Nirvana 'Nevermind' album from 1991.

Vig's tweet raises the question about what were they doing it for and just who is the "special guest".

Butch recently reformed his old band Garbage and they will release their 5th album 'Not Your Kind Of People' in May.

Novoselic has been involved with politics in recent years and authored the book 'Of Grunge and Government: Let's Fix This Broken Democracy'.

Grohl remains committed to Foo Fighters and his side project Them Crooked Vultures. He has also been making a documentary on Sound City Studios, where 'Nevermind' was recorded in Van Nuys. It is thought that the Butch, Dave, Krist recording may be related to Dave's documentary project.