The Logical Song singer is suffering from multiple myeloma, a cancer that forms in plasma cells which help the body fight infections.

Announcing the news on Tuesday (04Aug15), Davies says, "I was so looking forward to returning to Europe and playing with the band. I'm sorry to have to let down everyone who supported us overwhelmingly with the upcoming tour.

"Unfortunately health reasons have thrown me off track and I have to concentrate all my energy to the recovery."

The band was scheduled to embark on a European tour in Portugal in November (15). Dates were also set for Spain, Italy, Switzerland, Germany and the U.K.