Pop group Blue cancelled their farewell tour when singer Lee Ryan fell ill, but insist they have not split up.
The band members are expected to concentrate on solo projects
The band called off their European tour after Ryan developed nodules on his throat and was told to rest his voice.
A spokesperson said it was due to be their last tour before "taking a break" but they had not officially split and would try to reschedule the dates.
Ryan said: "I am gutted and very sorry to disappoint all our fans." The tour was scheduled to start on 11 March.
Ryan said the decision was "terrible timing" and he was "very upset".
"The situation is unavoidable as I have been told by doctors that if the tour takes place, I risk permanently damaging my voice," he said.
The spokesperson added that this was "not the end for the band". "They announced last year that they're taking a break, but they haven't officially split," she said.
The Best of Blue tour was due to include 12 UK shows plus concerts in Italy, Turkey and Germany. The Best of Blue album was released last year.
The quartet have enjoyed 10 UK top 10 singles including three number ones since June 2001. Their hits included collaborations with Sir Elton John and Stevie Wonder.
Ryan and bandmates Duncan James, Antony Costa and Simon Webbe are now expected to concentrate on solo projects.