Nightwish drummer Jukka Nevalainen is temporarily leaving the metal band to deal with personal health issues.

The Finnish group is in the middle of recording its new album, but Nevalainen has made the difficult decision to step away from the project.

Nevalainen posted a video on, on Wednesday (06Aug14) and said, "For a number of years, I have suffered from occasional but very difficult insomnia, something that has been my unwanted companion during many of our tours, too. I've done my best to try to control it or at least to cope with it... There is no 100 per cent cure for the problem.

"During the last month, it has become evident for me that due to my insomnia, I can't fulfill my duties as a musician in the way that I'd want and with the precision that the music deserves. Thus I have decided to step aside from my duties as the drummer of Nightwish during the recording of the forthcoming album and the subsequent tour. I will still be involved in managing the day-to-day affairs of the band, but the dearest and the most important thing, playing, is, for the time being, not possible. Time will tell what the future holds.

"On a personal level, my decision obviously feels indescribably sad. Fortunately, looking at it with some distance, it is 'just' part of the constant, inevitable ebb and flow of life. The sad things are part of it as well as the beautiful, unforgettable experiences and adventures that I've already had the pleasure to experience in spades. Surely, there will still be many adventures ahead, too."

"If beginning this was hard, so is ending it. So maybe I will just quote something fitting."

Wintersun drummer Kai Hahto is set to replace Nevalainen on the forthcoming album, but it is unclear whether he will also join Nightwish for a subsequent tour.