The Indonesian government's new policy of banning miners from exporting 14 metal ores unless they build a smelter could slow rising exports of the raw materials but may improve the country's downstream industry.

The new policy kicked off Sunday, prohibiting the miners from shipping 14 unprocessed metal ores, including copper, nickel, lead, silver, gold, zinc, chromium, bauxite, manganese, molybdenum, platinum, antimony, iron ore and sand iron. But, for miners who propose plans to build smelters, the government would allow them to continue exporting the unprocessed mining products with an average export tax of about 20 percent, Energy Minister Jero Wacik has said.

The new rule aimed at preventing the over exploitation of mining ores, export of which some of them have staggered by 500- 800 percent, ahead of the government planned policy in 2014 to totally prohibit miners from exporting unprocessed mining products, and to add their added values, Industry Ministry Minister MS. Hidayat has said.

The new policy is expected to follow the country's success in applying a similar rule in rattan industry. Indonesia's export of rattan-made products increased by 36 percent to 58 million U.S. dollars in the first quarter from a year earlier following the government ban on export of unprocessed rattan, Trade Minister Gita Wirjawan said on April 24.

The new regulation is expected to boost Indonesia's mining industry that has been lacking processing facilities. Meanwhile, President Susilo Bambang Yudhoyono has said that the government is aimed at seeking the possibility to boost revenue from mining sectors to help plug widening budget deficit, which has risen from the initial target of 1.5 percent of the GDP to 2.23 percent of the GDP this year.

The deficit may widen to more than 3 percent if without increases of the subsidized-oil prices or new steps taken by the government, Coordinating Minister for Economy Hatta Rajasa has said.

Besides, the government has announced policies of diverting most of the shares to local investors, which also aimed at boosting the roles of local investors in the mining industry.

Indonesia will remain attractive for foreign investors as it has abundant natural resources while the country's investment climate has improved. Indonesia was declared investment grade by Moody's Investor Service on Jan. 18, and its foreign direct investment rose by 30.3 percent to 51.5 trillion rupiah (some 5.6 billion U.S. dollars) at the first quarter from a year earlier.