You need to stop the sun from falling on it in the first place. If you don't there's a potential danger

Professor Michael Merrifield

But during the summer the sun will strike the shining surface and make it act like a magnifying glass.

Nottingham Playhouse say this is something that they were always aware of.

"We always knew there would be an issue with this and we planned for it," said a spokesman.

"We were always going to put a screen on the building for some months of the year, its just we didn't put planning permission in for it at the same time as the sculpture."

Sun screen

The problem will arise for a period of some eight weeks in mid-summer, with the greatest danger on the longest day.

Consultant astronomer for the projects design team Professor Michael Merrifield, who has been working on the project for some time said: "The mirror will focus light just the same as a magnifying glass does.

"The light gets focused down to a particular point and moves as the sun moves.

"You need to stop the sun from falling on it in the first place.

"If you don't there's a potential danger."

Planning permission is now being sought for a giant sunscreen to be attached to the listed building for some months of the year.

It will act as a backdrop to the sculpture and is in keeping with the work.

The Playhouse does not forsee any problems in obtaining the planning permission.

Anish Kapoor: Sky Mirror is part of a �1.2m refurbishment of Nottingham Playhouse

The opening of Sky Mirror has been delayed but the spokesman for the playhouse said this was to allow more time for polishing the dish which is taking place at Wellingborough.

Kapoor, who was born in Bombay but has spent much of his life in Britain, rose to prominence in the 1980s.

He won the Turner Prize in 1991 and has exhibited in the Tate Gallery, the Museum of Modern Art in New York and the Reina Sofia in Madrid.

Highly polished reflective discs and monumentally sized installations have long been part of his highly acclaimed work.

He is very interested by spirituality and has said that at the heart of his work is "the fear of oblivion, emptiness and the depiction of the void".

The opening of Sky Mirror has now been put back to Friday, 27 April.