China will adopt one of the world's strictest standards on vehicle exhaust emissions to further control air pollution, which will be conducted in two phases, starting separately in 2020 and 2023, the Ministry of Environmental Protection said last week.

Major regions with urgent demand in reducing air pollution could initiate the new emission standards earlier than scheduled, the statement from the national environment authority said on Friday.

All the light vehicles should follow the new China's National IV standard A starting from July 1, 2020, and then should follow the even stricter standard B starting from July 1, 2023, the statement said.

It added that these standards are one of the world's strictest, which could facilitate governments to cut down emissions.

Vehicle exhaust has become a major source of air pollutants in China, because the country has become the largest vehicle producer in the world since 2009, and is home to 170 million vehicles, the ministry said.

It's estimated that the total amount of major airborne pollutants such as carbon monoxide and nitrogen oxides, exceeded 45 million metric tons in 2015.

In other words, 86.9 percent of carbon monoxide and 92.2 percent of nitrogen oxides were from vehicles exhaust, it said.

In some cities, vehicle exhaust emissions have become the prime air pollution source, such as in Beijing.

In addition, the ministry said the technical support for the emission upgrade is ready and the petroleum plants will be ready to provide high quality petroleum for vehicles by 2020.