Chairman of the BMA in Northern Ireland, Dr Brian Patterson, spoke out hours after the first stage of the Health (Miscellaneous Provisions) Bill, which would create the loophole, was tabled at Stormont yesterday morning. It would permit actors to smoke where the artistic integrity of the performance makes it appropriate for them to do so.

Dr Patterson said the BMA "strongly objected to this proposed amendment on the grounds that artistic integrity of a performance is not a valid argument to allow smoking when the whole basis of the smoking legislation is to protect the public and all workers from the dangers of passive smoking.

"We are urging politicians to throw out this amendment."

The issue of whether actors should be exempt came to a head during last year's Edinburgh Festival when comedian Mel Smith was warned by Edinburgh City Council the theatre hosting the play he was starring in would be shut down if he lit up a Cuban cigar on-stage.

He was playing Winston Churchill in Allegiance.