Beijing will introduce new fuel standards on May 31 that municipal officials say are nearly on a par with the European Union's Euro V, the first Chinese city to do so.

All fuel sold by retailers in the Chinese capital will be required to adhere to the new standards, which are expected to reduce sulfur dioxide emissions from 50 to 10 milligrams per kilogram, according to the Beijing environmental protection bureau.

"The new Beijing V standard fuel, once implemented, will greatly reduce the amount of pollutants in the air, including the PM 2.5, (particulate matter with a diameter smaller than 2.5 micrometers) and improve the city's air quality," said Li Kunsheng, director of the bureau's vehicle management department. "The capital will become the first in the nation to meet the benchmark."

Li said Beijing's new standards will be close to the Euro V fuel standards. The European standards are the strictest in the world, according to Zhao Lijian, a researcher with the Energy Foundation.

According to Li, the most vital improvement of the new fuel is that it contains less sulfur, a major air pollutant.

"Excessive sulfur will lead to greater pollution," Li said.

The cleaner fuel will also increase engine efficiency and reduce fuel consumption, Li said.

According to experiments conducted by the China Automotive Technology and Research Center, the new fuel will cut pollutant emissions by 15 percent.

"People can imagine, the tremendous improvement of the city's air quality if all of the more than 5 million automotive vehicles in the city adopt the new petroleum," Li said.

The production of low-sulfur fuel will increase costs, said Fu Xingguo, an engineer at Sinopec Corp, China's largest oil refiner. However, the price of fuel will not be raised in the coming half year.

Fu also said Sinopec and China National Petroleum Corporation have mastered the technologies of petroleum refining, with the country's oil processing capacity reaching 450 million tons in the year 2011.

"However, we are still challenged by the shortage of crude oil resources for the moment," he said.

Fu said some 56.5 percent of the oil was imported last year and had a high sulfur content.

Car emissions have been increasing over the past few decades. "The exhaust emitted by automotive vehicles has replaced the coal-boilers to become the biggest source of air pollution in Beijing," Du Shaozhong, former deputy director for the Beijing environmental protection bureau said in February.

Beijing has more than 5 million vehicles and 10 million registered drivers.

According to Li, drivers from other provinces also have to pump the refined gasoline or diesel fuel when coming into the capital.

"This is the rule of the city," he said.

Ma Jun, director of the Institute of Public and Environmental Affairs, said improved fuel quality and emission standards are key to improving the air quality.

"With many cities nationwide still adopting less strict fuel standards, Beijing is very much ahead of them," he said.

Shanghai is adopting the China IV fuel standards and is considering implementing strict standards in 2013, according to the Shanghai environmental protection bureau.

However, Ma said execution and joint efforts with neighboring provinces are equally important.