East China's Zhejiang Province will penalize local cities that fail to meet PM2.5 requirements from next year, the province's latest efforts to improve air quality.

In a regulation released Thursday by the Zhejiang provincial government, the annual average level of PM2.5, fine particles measuring 2.5 microns or less in diameter that can imbed deep in people's lungs, is not allowed to rise more than 10 percent in one year or over several years in each city in the province.

Those cities reporting worse air quality could be fined up to 5 million yuan (813,000 U.S. dollars).

Meanwhile, unless they see PM2.5 levels improve over two consecutive quarters, cities in Zhejiang will not be allowed to greenlight heavy-polluting industrial projects for the following year, according to the regulation.

Cities that report an annual drop in PM2.5 of more than 10 percent could get a reward of up to 5 million yuan, it said.

All county seats will be subject to the fines and rewards starting in 2015.

China -- especially its booming industrial regions -- is struggling to clean up air that has been polluted by decades of industry-driven economic growth as well as rapid increases in car ownership in cities.