HANOI, July 3 (Xinhua) -- The export tax on coal will rise by 3 percent to reach 13 percent from July 7, urging Vietnam National Coal and Mineral Industries Group (Vinacomin) to cut its shipments by more than half to around 400,000-500,000 tons a month.

According to the group's Deputy General Director Nguyen Van Bien, it will be a sharp fall compared to the 1.2-1.3 million tons currently being exported each month.

With the new export tax rise, in the last six months of this year, total amount of coal exported by the group is estimated to reach 2-3 million tons.

This will result in the country's coal exports this year falling to 10.5 million tons, or 4-5 million tons less than 2012.

Vietnam's tariff on coal exports are among the highest in the world. While coal now has to compete with other new energy sources, some of them renewable, coal mining in Vietnam is facing difficulties. Coal mines have become deeper with many over 300 meters deep, and coal miners risk being trapped by flooding, fire or collapses.

In the first six months of this year, coal consumption stood at 21.5 million tons, an increase of 9.15 percent against the same period last year. The country exported around 7.8 million tons of coal, earning 546 million U.S. dollars, an increase of 7.5 percent in volume, but down 14.7 percent in value, year on year, according to the General Statistics Office.