Basketball superstar Yao Ming and famed soprano Peng Liyuan Monday became the new faces of China's anti-smoking campaign, which health officials said is still a tough task in the world's largest tobacco market.

Both Yao and Peng were not present at a meeting of the Chinese Association on Tobacco Control (CATC) in Beijing, where their representatives received certificates from the association.

It is believed that they would appear in public service advertisements persuading the people not to smoke at public places or to give up the smoking habit.

Yao, the most successful Chinese NBA player, appeared in a 2006 advert asking the Chinese not to eat shark fin soup as part of a WildAid campaign to save the endangered fish from extinction. Peng Liyuan also joined a public awareness campaign against HIV/AIDS-related stigma.

"We hope the celebrities (like Yao Ming and Peng Liyuan) would inspire more people to join in anti-smoking activities. The public should be advised to lead a healthier life without the influence of tobacco use," said Xu Guihua, deputy director of the CATC.

It is estimated that about 350 million Chinese, or nearly 27 percent of the country's total population, are consumers of one third of tobacco products around the world.

Each year about one million Chinese die from lung cancer and cardiovascular diseases that can be directly linked to tobacco use, according to the CATC.

Passive smoking, commonly known as secondhand smoke, also put the health of additional 540 million Chinese under threat, partly due to weak enforcement of smoking ban in public places.

Vice health minister and CATC's director Huang Jiefu admitted that China had made "slow progress" in implementing the World Health Organization Framework Convention on Tobacco Control, which was endorsed by China and became effective in January 2006.

The most urgent task was to enforce a smoking ban at all indoor public places and workplaces by 2011 in line with the convention's requirement, Huang said.

But he said tobacco control would be a "long term and arduous" mission in China. In many places tobacco industry is encouraged as a major contributor of tax and revenue of local governments.

Between 2004 and 2008 the output of tobacco products across China rose 18.4 percent.

The CATC's anti-smoking campaign was previously supported by other Chinese celebrities including table tennis player and Olympic gold medalist Zhang Yining and actor Pu Cunxin. Pu also joined some 40 actors and actresses to launch a campaign to advocate smoking-free films.