LANZHOU - Authorities in the northwestern Chinese city of Lanzhou Saturday introduced a two-month odd-even traffic restriction in its urban center effective Sunday, amid the latest efforts to curb severe winter pollution.

Cars will be banned from roads from 7 a.m. to 8 p.m. on alternate days in the period to January 10 next year depending on whether their number plates end in odd or even numbers, the Lanzhou city government said in a statement.

Police cars, fire trucks, ambulances, emergency repair vehicles and taxies, however, are not subject to the ban, it said.

The city unveiled measures in October ordering the launch of the odd-even traffic ban if local air quality index outnumbers 100 while the PM2.5 concentration exceeds 75 micrograms per cubic meter for three consecutive days.

Amid other measures to tackle the notorious pollution, the city government also has encouraged more use of gas rather than coal, cracked down on outdoor barbecue and closed highly-polluting small plants.

Lanzhou, capital of Gansu Province, is situated in the river valley of the Yellow River, the country's second-largest, and is surrounded by mountains. Therefore, the geographical conditions hinder the dispersal of pollutants.