A innovative scheme for avoiding a ban on smoking in public places has been developed in Japan.

The SmoCar consists of a mobile trailer in which smokers can get together and puff away in peace. Two of the smoking 'rooms' have been deployed by Japan Tobacco Incorporated, the world's third largest tobacco producer.

One of the SmoCars travelled to event locations throughout Japan last year, a letter to the British Medical Journal reported. They included a classic car race in Gunma, and the Tokyo Motor Show.

But the development has met with opposition in Japan. Professor Hiroshi Kawane, from the Japanese Red Cross Hiroshima College of Nursing, who wrote the letter, said: "Japan Tobacco claims that SmoCar has been developed as part of the company's initiative to increase co-existence between smokers and non-smokers in public places.

"I think secondhand smoke combined with exhaust fumes from SmoCar has become a health hazard for non-smokers in the vicinity of the car."