Health authorities in Shanghai say that non-smoking areas will be expanded from public places to all indoor buildings by 2011 to protect people's health.

Officials from the Shanghai Patriotic Health Campaign Commission Office made the announcement as part of a campaign to turn Shanghai into a "Healthy City."

Medical research shows that people working indoors with regular smokers are more likely to develop lung cancer from breathing secondhand smoke.

But the move has sparked varied responses from the general public.

"It seems quite difficult. Many people have a strong addiction to smoking. I think increasing warnings about smoking is much better."

"We all suffer from smoking, I think, no matter if it's smokers themselves or people around them. This campaign will run into some obstacles, but it will work out gradually."

Figures from the municipality indicate that about 300 restaurants and hotels in the city have already installed non-smoking areas. Another 6,000 large and medium-sized restaurants and hotels will have non-smoking areas by 2010.

The city will also introduce tougher measures on smoking with the first anti-smoking laws now under discussion by the Shanghai Health Bureau and the Shanghai Municipal People's Congress.