A survey by the Chinese Health Ministry has revealed that China's smoking ban in indoor public places is poorly observed, said a senior health official in Beijing on Wednesday.

Wang Suyang, director of the National Center for Health Inspection and Supervision under the ministry, said that under the survey program, the center has monitored smoking ban enforcement in 144 restaurants and 140 hotels and lodgings in Heilongjiang, Shandong and Gansu provinces and Xinjiang Uygur Autonomous Region over the past year.

"In these places, anti-smoking enforcement has been slack. Moreover, only 6.1 percent of the businesses have designated smoking areas, and only 1.4 percent have anti-smoking warning signs to alert smokers," said Wang.

China enacted an indoor smoking ban in public venues starting May, 2011.

Experts pointed out that the law's enforcement faces challenges as it does not have specific clauses on enforcement procedures and penalties for indoor smoking.

Wang said that 90 percent of smokers in the surveyed areas admitted that they would have put out cigarettes if they were told not to smoke.

China is the largest tobacco-producing and consuming country in the world, with more than 300 million smokers and another 740 million people affected by passive smoking, official figures show. About 1 million Chinese people die from tobacco-related illnesses annually.

Wang said the country's future smoking controls should make it clear that business owners will be checked if indoor smoking is reported in their establishments.