Black Sabbath have cancelled all but one date on the European leg of their world tour, due to guitarist Tony Iommi's ongoing treatment for lymphoma.
The band will now only play their headline show at Download festival on June 10 but other dates planned in Europe will now be billed as 'Ozzy and Friends'.
The singer will be joined by Black Sabbath's Geezer Butler and longtime Ozzy collaborator Zakk Wylde, as well as a number of special guests, including Slash.
A statement from the band said: "Tony Iommi continues to make excellent progress and is looking forward to getting back out on the road. Meanwhile, Black Sabbth continue to write and record music in the UK for their upcoming album."
Ozzy & Friends/Black Sabbath will play the following dates:
Helsinki Hartwall Arena - May 23
Stockholm Stadium - 25
Denmark Jelling Festival - 27
Norway Bergen Calling Festival - 29
Oslo Spektrum - 31
Malmo Stadium - June 2
Dortmund Westhalenhalle - 4
O2 Arena Prague - 6
Download festival - 10 - Black Sabbath
Spain Azkena Rock Festival - 15
France Clisson Hellfest - 17
Belgium Graspop Metal Meeting - 22
Italy Gods Of Metal Festival - 24
Vienna Stadthalle - 26
Belgrade USCE Park - 28
Greece Rockwave Festival-Terra - July 1