The unexpected news of a fuel price increase late yesterday weighed heavily on the stock market this morning as both stock indices sunk into the red.

The ministries of Finance and Industry and Trade yesterday afternoon announced they had allowed petrol businesses to increase fuel retail price. Petrol surged to the record price of more than VND24,500 (US$1.17) per litre, breaking the previous record of VND23,800 set in April 2012.

On the HCM City Stock Exchange, the VN-Index was down 0.22 per cent from yesterday's close, standing at 489.60 points by the end of the morning as decliners outnumbered advancers by 147-42.

Many of the top 30 shares by market capitalisation and liquidity slumped, dragging the VN30 down 0.32 per cent to 550.18 points.

Although gas prices increased, shares of Petrolimex's companies did not rise follow, decreasing by more than 1 per cent for Petrolimex Gas Corporation (PGC) and Petrolimex Tanker Co (PJT).

Trading was sluggish with the value of trades just half of that seen yesterday morning, reaching VND363.5 billion ($17.3 million).

Tan Tao Investment-Industry led the market activity with 2.6 million shares changing hands, sinking 3 per cent to VND6,500 a share.

On the Ha Noi Stock Exchange, the HNX-Index also slid 1.24 per cent to 59.56 points on a turnover of VND203.7 billion ($9.7 million).

Losers also swamped gainers by 132-38.

Sai Gon-Ha Noi Bank (SHB) was the most active code this morning on trades of 5.3 million shares, falling 1.52 per cent to VND6,500 a share.

Trading will resume at 1pm.