Gas prices fell VNĐ69,000 (US$3) per 12kg canister on Wednesday as global crude oil prices dropped sharply.
HCM City authorities are strengthening control over the trade of oil and petroleum products to ensure safety at petrol stations and gas shops that sell flammable substances.
Gas prices in the south increased by VNĐ17,000 (72 US cents) for a 12kg canister on Friday (March 1).
The Ministry of Industry and Trade (MoIT) will submit a draft decree to ease the entry of businesses into the gas trading market.
The draft decree to replace Decree No 19/2016/NĐ-CP on gas trading has stirred controversy among gas traders, heard attendants at a conference held in Hà Nội on Wednesday.
Some 800 small and medium sized gas trading companies have submitted a proposal to the Prime Minister Nguyễn Xuân Phúc and Minister of Industry and Trade Trần Tuấn Anh on gas trading requirements.