The National Development and Reform Commission, the country's planning agency, on Friday urged oil companies to help "maintain social stability and promote economic development" by increasing refinery output and stepping up new projects to ensure stable supplies.
It said roadways, cities, farmers and public utilities should receive priority. The temporary suspension of diesel shipments, "in principle," does not apply, however, to the territories of Hong Kong and Macau.
Past shortages have often reflected refineries' reluctance to increase output at times when rises in global crude oil prices have outpaced the government-controlled prices in the domestic market.
But state-set gasoline and diesel prices are at a record high following an increase of about 5 percent on April 6 to reflect higher global crude prices.
The surge in demand is more likely linked to widespread use of diesel-fueled generators to keep factories running through power outages.
Electricity utilities have been pushing for a rate hike to reflect higher costs due mainly to a surge in the price of coal, which fuels about three-quarters of the country's power generators. But the shortages have been deepened by weak hydroelectric supplies due to a severe drought in much of central and eastern China.