Slater needs an extra day to recover

Slater, 34, was taken ill while rehearsing One Flew Over the Cuckoo's Nest in London.

The production, which was due to open on Friday in Edinburgh, was to run for three weeks in conjunction with the city's annual arts festival.

The actor has been advised to rest for one more day which has led to the opening night being postponed.

Producer Nica Burns said: "We so hoped we would be able to make the first performance but poor Christian's chickenpox has simply been too virulent.

"In order to safeguard the rest of the run we are having to take the doctor's advice to let Christian recover for one more day. (His character) RP McMurphy is an enormous part requiring great energy."

Ms Burns had earlier said that Slater had caught the chickenpox from fellow cast member Felix Dexter who had come down with it during rehearsals.

Other co-stars in the play include The Office's Mackenzie Crook and Frances Barber.

Following a three-week run at the Assembly Rooms in Edinburgh, One Flew Over the Cuckoo's Nest will transfer to the Gielgud Theatre in London.