Metallica have cancelled their tour so James Hetfield can return to rehab.

James Hetfield

James Hetfield

The rockers were due to perform in Australia and New Zealand on their upcoming tour but Lars Ulrich, Kirk Hammett and Robert Trujillo have revealed in a statement that it has been axed as their bandmate has returned to rehab to "work on his recovery".

They said in a statement posted on Twitter: "A Note from Lars, Kirk, and Rob. We are truly sorry to inform our fans and friends that we must postpone our upcoming tour of Australia and New Zealand.

"As most of you probably know, our brother James has been struggling with addiction on and off for many years. He has now, unfortunately, had to re-enter a treatment program to work on his recovery again.

"We fully intend to make our way to your part of the world as soon as health and schedule permit. We'll let you know as soon as we can.

"Once again, we are devastated that we have inconvenienced so many of you, especially our most loyal fans who travel great distances to experience our shows. We appreciate your understanding and support for James & thank you for being a part of our Metallica family.

"All tickets purchased to the shows in Australia and New Zealand, including Enhanced Experiences and Black Tickets, will be fully refunded."

The tour was due to begin October 17th in Perth, Australia and conclude November 2nd in Auckland, New Zealand.

Currently, the band's 2020 commitments are still scheduled to go ahead, including a March 28th benefit show in San Francisco and a South American tour in April.

James' battle with addiction was documented in the 2004 movie 'Some Kind Of Monster', and he spent time in rehab after the film was released.

Asked previously if the film was difficult to watch, the 56-year-old star said: "A lot of times I'm not really comfortable with myself, seeing myself in the situations. But, man, I learned a lot about what I don't like about me, which was good - and I think everyone involved pretty much felt the same way about themselves."

In 2017, Hetfield revealed he had been sober for 15 years and said fear was a huge motivator in his recovery.

He said: "Fear was a big motivator in that for me. Losing my family, that was the thing that scared me so much, that was the bottom I hit, that my family is going to go away because of my behaviours that I brought home from the road. I got kicked out of my house by my wife, I was living on my own somewhere, I did not want that. Maybe as part of my upbringing, my family kind of disintegrated when I was a kid. Father left, mother passed away, had to live with my brother, and then kind of just, where did my stuff go? It just kind of floated away, and I do not want that happening. No matter what's going on, we're going to talk this stuff out, and make it work."