Smog and haze affecting Central and East China won't clear before Dec 8, the Environmental Protection Ministry said on Dec 4.

The smog arrived in the Yangtze River Delta region on Nov 30, where the air quality in 12 cities out of 25 was rated as severely polluted by Dec 1.

Beijing, Tianjin and Hebei province have also been affected by smog and haze since Dec 1, although the Chinese capital has not been hit as badly as several other cities, including Shijiazhuang and Xingtai in Hebei and Jining in Shandong, which have all seen heavy air pollution.

Some northeastern cities have also been blanketed in thick smog and haze, including Harbin, the capital of Heilongjiang province.

The ministry said the main reasons for the pollution include weather conditions that cause pollutants to accumulate and remain in the air, and a sharp increase in emissions from coal-burning in the heating season.