Image caption China has more smokers than any other country

A ban on smoking in public places has come into force in China - home to a third of the world's smokers.

The move is aimed at curbing the number of deaths from smoking-related diseases, running at a million a year.

But the new rules have been criticised because they do not include punishments for those who choose to ignore them.

Business owners often resent efforts to force them to ban smoking on their premises, because many customers do not like the rules and complain.

The new rules prohibit smoking in places like restaurants, hotels, railway stations or theatres, but not at the office.

Employers will be obliged to warn staff of the dangers of smoking but not to forbid them from lighting up at their desks.

Resistance

Shanghai imposed similar rules a year ago, but people do not seem to take much notice of them.

Often you find people smoking at the next table while you are eating your meal or having a drink in a bar.

The problem is the regulations do not specify punishments for businesses or individuals who flout them.

It appears that many Chinese people are unaware of the dangers of smoking. Research suggests only one in four knows the harm cigarettes or second-hand smoke can cause.

Officials say they have to try to persuade people not to smoke to try to reduce the numbers dying from smoking related diseases.

At the same time though the government makes a lot of money from the sales of cigarettes by the state-owned firm that makes and sells all tobacco products throughout the country.