OREANDA-NEWS. March 16, 2015. Vietnam's benchmark VN Index ended down 0.4 percent on Friday, a one-month low, as investors sold shares of energy companies following a parliamentary panel's decision to triple environment tax on oil products.

A National Assembly committee approved a Finance Ministry plan on March 10 to triple the environment tax on petrol and most oil products from May 1, the government said on Wednesday.

The index closed at the session low of 586.10, its lowest since Feb. 12. Volumes rose 17.6 percent from Thursday to 97.28 million shares, above the five-day average of 94.07 million shares, based on Thomson Reuters data.

PetroVietnam Gas, the country's largest listed firm, dropped 1.3 percent, PV Drilling lost 1.8 percent and PV Trans dipped 0.7 percent.