Metallica and Linkin Park are both working on new albums, producer Rick Rubin has revealed.
Rubin told Billboard Linkin Park, who recently headlined Donington's Download festival, had been “in the studio writing” the follow-up to 2010's 'A Thousand Suns'.
He said he was having once a week meeting with the band and that they were currently making good progress.
“On ('A Thousand Suns') there were still a lot of irons in the fire,” he added. “We knew, 'OK, we can't do this forever. Let's leave this batch and we'll come back and address it when we start up again.' "
Speaking about Metallica, Rubin said he had recently had a meeting with the group's drummer Lars Ulrich in San Franciso.
“I'm still sort of thinking about what that is going to be,” he said.
“I'll ask a lot of questions and we'll probably listen to some of the riffs that they've been writing. Usually I'll hear something that will sort of indicate the direction and then we'll talk about it from there."
Metallica recently announced details of a new album with Lou Reed, which Rubin was not involved in.
Download Festival 2011 - The Best Bits
You can keep up to date with all the latest news from Gigwise by following us on Twitter and liking us on Facebook.

Red Hot Chili Peppers Chad Smith: People Always Think I'm Will Ferrell
Alex Turner Fights It Out With Jared Leto For Hottest Male Vote
Lil' Wayne's 'Tha Carter IV' Sells 964,000 Copies To Score Number One
Adele Cancels Cardiff Gig Tonight (September 7) And Blackpool Tomorrow (8)
Metallica And Lou Reed Announce Tracklisting For 'Lulu'
Metallica Yankee Stadium Gig Sparks Riot Fears
Bestival Festival 2011: The 25 Must-See Acts
Foo Fighters' Dave Grohl To Muse's Matt Bellamy: The Best Guitarist Sex Faces
GQ Men Of The Year Awards 2011: Photos With U2, Tinie Tempah And More