Beijing will reduce coal consumption by 4 million tonnes, shut down 300 factories and retire 200,000 heavily polluting vehicles in 2015, said Li Shixiang, executive vice mayor of Beijing and a deputy to the National People's Congress Friday.

Cutting coal burning, limiting the growing number of cars, curbing environmental pollution and reducing dust emission will continue to be the four major measures to control air pollution in the city, Li said.

Beijing and its neighboring Tianjin Municipality and Heibei Province had for the first time made a coordinating plan in treating air pollution last year, which has achieved some positive results.

According to Li, keeping the sky blue will be a long-term task that requires both strict law enforcement and constant efforts.

Beijing has closed or removed 294 polluting factories in 2014. But the city will still use 15 million tonnes of coal this year even after the reduction.

Financial subsidies are in place to ensure 200,000 heavily polluting vehicles be retired within the year.

Land development will be strictly controlled so as to limit the number of construction sites in the city. In addition, compulsive dust reduction measures are implemented on every construction site.

"We are confident that we can stick to the four measures," Li added.