Those of RON 95-III and E5 RON 92 were cut by 390 VND and 340 VND to 23,530 VND (0.97 USD) and 22,270 VND per litre, respectively.
This is the first reduction after two increases in a row in late October and early November.
Meanwhile, the prices of diesel, kerosene and mazut were reduced to between 15,620 and 21,510 per litre or kilogram.
The ministries decided not to use the petrol and oil price stabilisation fund.
Since the beginning of this year, petrol prices have undergone 32 adjustments, with 18 up, 10 down, and four unchanged.
The price adjustment is intended to ensure that the fluctuation of petrol and gas prices in the country is in line with changes in prices in the world while encouraging the use of biofuel as well as minimising negative impact on socio-economic development, production and business activities, among others.