A stricter vehicle emission standard for Beijing’s 5m motor vehicles will be introduced next year, said Zhang Lijun, vice-minister of environmental protection. The national standard V for vehicle emission will be brought in at around the same time similar standards are imposed in developed countries, he added.

The number of vehicles on Beijing’s roads increased from 1m in 1997 to 4.76m at the end of 2010, reported Xinhua, leading to widespread congestion and rising exhaust emissions.

Research has shown that more than three-quarters of total air pollution in China’s largest cities comes from vehicle carbon monoxide and hydrocarbon emissions. The government in Beijing has raised vehicle emission standards four times since standard I was introduced in 1999.