BEIJING (Canadian Press) -- China is tightening smoking regulations to ban lighting up in any indoor public spaces in seven provincial capitals, the latest sign of rising health awareness in the world's largest tobacco-consuming nation.

The success of the effort may provide the best indicator yet as to whether broad efforts to restrict tobacco use can overcome stiff resistance from retailers and some local governments, which profit significantly from tobacco taxes.

Smoking is a huge business in China: 2 trillion cigarettes are sold in the country every year. The country accounts for more than one-quarter of the world's 1.3 billion smokers, with about 60 per cent of Chinese men and 3 per cent of women indulging in the habit.

China nominally banned smoking in public places indoors four years ago under a U.N. treaty, but enforcement is lacking.

"Our aim is to make 100 per cent of the environment in indoor public places and workplaces smoke-free in these seven cities," Qu Yan, an official with the government's Center for Disease Control and Prevention, told The Associated Press on Monday.

Cities targeted include some of China's biggest commercial centres - such as Tianjin on the northern coast and the megacity of Chongqing in the southwest - where smoking and breathing in secondhand smoke add to health threats from traffic, industrial waste, and polluted air and water.

Qu said that goal will require enacting or amending local smoking regulations. The CDC hopes to have those changes in place by the end of 2011, she said.

Gan Quan, head of anti-smoking programs for the International Union Against Tuberculosis and Lung Disease, said it was unclear how effective the move would be.

"This involves efforts from a lot of different directions, so it's very hard to say how confident we are about the program's success," Gan said.

Local governments that rely on the income from cigarette sales sometimes push consumption in spite of a partial ban on tobacco advertising.

A rural county in central Hubei province last year sparked a public outcry after pushing the sale of more than 230,000 packs of locally produced cigarettes a year to boost tax revenues. The move was called off in the face of public criticism.

Taxes from tobacco sales topped 416 billion yuan ($61 billion) last year, up 26.2 per cent from 2008, according to a report issued last week by the state tobacco industry regulator. Interest on government loans to the industry added another 97 billion yuan ($14 billion).

"The big increase in tax income from the tobacco industry is actively contributing to the security of government finances," a spokesman for the regulator, Zhang Xiulian, was quoted as saying on its Web site.

The Canadian Press, 2010