BEIJING — China will raise the retail prices of gasoline and diesel from May 12, the sixth increase this year, the country’s top economic planning body announced on May 11.

As international oil prices have risen, the retail prices of gasoline and diesel will rise by 170 yuan (about $26.8) and 165 yuan per ton, respectively, according to the National Development and Reform Commission (NDRC).

Under the current pricing mechanism, if international crude oil prices change by more than 50 yuan per ton and remain at that level for 10 working days, the prices of refined oil products such as gasoline and diesel in China are adjusted accordingly.

Oil prices have trended upwards as investors saw global oil supply decline.

US President Donald Trump said on May 8 the country would quit the Iran nuclear deal and restore sanctions on oil producers. Investors worried that reinstated sanctions could contribute to tighter global oil inventories.

The NDRC said it would closely monitor the effects of the current pricing mechanism and make changes in response to global fluctuations.

It has asked major Chinese oil companies, including China National Petroleum Corp, China Petrochemical Corp, and China National Offshore Oil Corp, to ensure stable supply and pricing.