Vietnam's main stock index fell by the most in about 15 months on Monday after the government said at the weekend it would raise electricity prices a record 15.3 percent and enhance measures to curb double-digit inflation.

The Ho Chi Minh Stock Exchange index shed 4 percent to close at 483.68 points, its lowest close since January 12. The fall was the biggest on the country's main exchange since late November 2009, according to Reuters data.
The index was down 4.4 percent before rebounding slightly in the final minutes of the trading session. The smaller Hanoi stock exchange index slipped 5.6 percent.
On Saturday, state media reported the government had approved an average increase in electricity prices of 15.28 percent, to take effect on March 1.
"The panicked sentiment led to a broad sell-off," said Quach Manh Hao, Deputy Director of Thang Long Securities Company. "However, this is a golden chance for cash-rich funds to disburse now."
In Ho Chi Minh City, 50.54 million shares traded hands with a value of VND1.1 trillion.
"Market sentiment is getting much more sour, which may lead to a continued sell-off in the coming couple of sessions," said Nguyen Hoang Long, head of the investment department at An Binh Securities.
The Hanoi market crashed through a support level of 96.76 points, he said, and was "unlikely to see any positive development from now until the start of the third quarter."
In recent weeks, Vietnamese authorities have begun to try to address festering macroeconomic imbalances that have worried investors and played a part in decisions by Standard & Poor's, Moody's and Fitch to cut the country's sovereign ratings last year.
The consumer price index hit 12.2 percent in January and economists widely expected it to remain high for most of the year.
On February 11 the central bank devalued the currency by 8.5 percent, its biggest move since the 1997-8 Asian Financial Crisis, in an effort to re-align official and black market exchange rates.
Last week the State Bank of Vietnam increased by 200 basis points a key interest rate, the refinance rate, in a move to curb inflation and state media reported on Monday governor Nguyen Van Giau said he had won approval from the government to lower the national credit growth target to 18-19 percent from 23 percent.
Businesses and economists have said the electricity price rise would exacerbate inflationary pressures.
The government has been considering a possible increase to the retail price of petrol, too, and there have been reports in state media about filling stations closing or raising prices on their own in anticipation of such a move.