Bee Gees star Robin Gibb sparked fresh fears for his health by pulling out of a charity performance at the last minute on Thursday (27Oct11).
The ailing singer has been fighting to get better since he was hospitalised with abdominal pains and treated for inflammation of the colon earlier this month (Oct11).
The 61 year old was due to perform a charity single at an event for the Royal British Legion in London on Thursday but cancelled, citing ill health.
A source tells Britain's Daily Mirror, "He took a turn for the worse and couldn't physically do it in his current condition."
Gibb shocked fans with his frail and gaunt appearance after leaving his sick bed on Monday (24Oct11) to perform on U.K. TV.