After several weeks of blue skies, the smog seems to be back in the capital, Wang Guoqing, spokesman for the fourth session of the 12th Chinese People's Political Consultative Conference (CPPCC) National Committee, said on Wednesday.

In the first 10 months, Beijing saw days with good air-quality recordings increase by 31 year-on-year. But in November and December, the number of days with good air quality fell by 14, year-on-year.

"China has conducted a series of efforts to control air pollution, which is closely related to economic development," he said at a press conference.

"Governments need to notice the urgency in alleviating pollution to take tough restrictions but also treat curbing efforts as a long-term campaign."

To curb air pollution, governments at all levels need to issue more policies to lead efforts and push forward the optimization of the economic structure, Wang said.

He added that the companies should improve their production methods to reduce emissions of airborne pollutants.

The public is also encouraged to take environmental-friendly transport more frequently, like buses and bicycles. To facilitate the growth of green traffic, governments need to issue clear policies.

He said if comprehensive measures were implemented well to improve air quality, blue skies will not be far away.