The price of popular gasoline RON 95 and biofuel E5 RON 92 both rose 2.3 percent to VND30,650 and VND29,630, respectively. ($1 = VND23,165)
But diesel, kerosene and mazut cost 3.1-4.7 percent less.
This is the first time ever gasoline prices in Vietnam surpassed the VND30,000-mark. Monday's was the fifth hike since April 12 without a downward adjustment in between.
Compared to the beginning of 2022, a liter of gasoline now costs 28 percent more, despite the government's environmental tax cut.
The tax, a flat VND4,000 a liter, has been halved since April 1.
The Ministry of Industry and Trade and the Ministry of Finance, which are responsible for regulating gas prices, have attributed the increase in domestic prices to limited supply on the global market following Western embargoes on Russian oil and the U.S.' declining oil reserves.
On the global market, oil prices surged by 0.4 percent to $110.28 a barrel Friday. At the time of writing, its prices are hovering above $111 a barrel.
Vietnam authorities make gasoline price adjustments on the first, 11th and 21st day of the month; therefore, changes follow global movements after a certain delay.