Around six million older, polluting vehicles are being planned to be taken off the road by China's government this year in an effort to revive stalled progress toward cleaning up smog-choked cities, the Associated Press reported.

To switch to selling only the cleanest grades of gasoline and diesel, the plan also calls for filling stations in Beijing, Shanghai and other major cities, according to a Cabinet statement issued Monday.

After China failed to meet official pollution-reduction goals for 2011-2013, the development was made, the statement said.

It said vehicles registered before 2005 that fail to meet cleaner emissions standards will be "phased out," though it did not say how.

The country's environmental situation was described as "extremely grim."

"China's major cities are smothered in eye-searing smog," the AP reported. "The country has some of the world's strictest emissions standards, but authorities have refrained from enforcing them until now to avoid forcing older, pollution-belching trucks off the road and hurting small businesses."

"Monday's announcement suggests authorities have settled that conflict in favor of environmental protection following reports on the mounting health and economic costs of pollution."

With about 240 million vehicles on the country's road, half are reported to be passenger cars, according to the Ministry of Public Security.

"China is the world's biggest auto market by number of vehicles sold. Sales rose 15.7 percent last year to 17.9 million vehicles," according to the AP. "Sales growth is slowing but analysts still expect an increase of 8 to 10 percent this year."

"Taxi fleets and public buses in major cities have been required to switch to cleaner-burning natural gas or battery power. The government is promoting development of an electric car manufacturing industry."

In an attempt to reduce smog and traffic congestion, city governments in Beijing, Shanghai and other major cities have enforced curbs on new vehicle restrictions.