Hetfield made the revelation during an interview with Abu Dhabi's That's Entertainment, "We haven't even started writing it," Hetfield said.

"We're going through riffs. We have, like, 800-and-something riffs we're going through � lots of ideas. We're really excited about it, but doing concerts here and there, trying to get back in the studio and get some stuff done, it's all really exciting.

"But it gets done on Metallica time, which is not really scheduled. When it's done, it's done and when it's good, then it will be done."

Hetfield's comments mirror drummer Lars Ulrich's recent revelation that he would be surprised in the band released the album before 2015 due to their current schedule.