By Ichiro Suzuki and Masumi Suga

Oct. 1 (Bloomberg) -- Sojitz Corp., a Japanese trading company, and Nittetsu Mining Co. gained government approval from Laos to explore for copper as demand for commodities increases, four people involved in the talks said.

The companies will explore an area near the Thai border, about 100 kilometers (62 miles) west of the capital Vientiane, a company executive and a Japanese trade official said, who asked not to be named because the approval, gained on Sept. 15, has not been made public.

Japanese companies are vying with overseas rivals to secure resources on speculation global demand for raw materials will increase, fueled by growth in China. Gold and copper account for more than half of Laos’ exports, which make up about a third of the country’s economy.

Sojitz spokesman Yoshikazu Ichikawa and Nittetsu Mining Managing Director Nobuhide Miyazaki declined to comment on the Laos exploration. Khenthong Nuanthasing, a Lao government spokesman, said he has no comment.

The Tokyo-based companies plan to do preliminary research, exploration and a feasibility study over six years, the people said.

Copper for delivery in three months on the London Metal Exchange has doubled this year fueled by China’s buying and speculation that a recovery in the global economy will increase consumption of raw materials. The metal traded at $6,166 a metric ton at 7:29 p.m. Tokyo time yesterday.

Pan Pacific Copper Co., Japan’s biggest smelter of the metal, plans to spend $1.86 billion on the development of a mine in Chile, the company said Sept 9.

To contact the reporters on this story: Masumi Suga in Tokyo at msuga@bloomberg.net; Ichiro Suzuki in Tokyo at isuzuki@bloomberg.net.