Ten Year Production Period Extension for Concessions in the Gulf of Thailand

October 29, 2007 Project

Mitsui Oil Exploration Co., Ltd. ("MOECO", Head office: Hibiya Central Bldg. 2-9, Nishi Shimbashi 1-Chome, Minato-ku, Tokyo, JAPAN / President: Mr. Yoshiyuki Kagawa) is pleased to announce that the Thai Cabinet has approved a 10-year extension of the production period under petroleum concessions covering blocks 10, 11, 12 and 13 in the Gulf of Thailand (Total area: approximately 4,572 square kilometers) after their expiry in 2012. The concessionaires in the blocks are Chevron, PTT Exploration and Production Public Company Limited (PTTEP) and MOECO.

The Thai Ministry of Energy has signed a Supplementary Concession extending the production period for areas contained in these four offshore blocks in the Gulf of Thailand for an additional ten years from 2012 to 2022.

The above mentioned blocks contain prolific oil and gas fields such as the Erawan, Satun, Funan, Banpot, Plamuk, Yala, Pla Daeng, and Platong operating areas in the Gulf of Thailand. Daily production from the concessions as of the end of July in 2007 is approximately 60,000 barrels of condensate and crude oil, and 1,000 million cubic feet of gas. MOECO currently holds a 20 percent working interest in the concession area known as "U1"; 30 percent in "U2"; and 23.75 percent in "U3".

This production period extension is the first of its kind in Thailand and represents a significant historical event in the Thai energy industry and is the culmination of many years of effort by the operator and joint venture parties and also recognizes the long history of joint operations based on a high regard for environmental protection, the provision of a long-term stable energy supply and the expansion of local employment for the growth of Thailand's economy. In addition, the extension represents an exceptional example of the benefits of maintaining a mutually beneficial relationship between oil producing countries and investors such as oil companies based on a spirit of mutual understanding.

This 10 year extension will enable the concessionaires to meet the strong energy demand of the Kingdom of Thailand based on its growing economy of approximately 4 or 5 % per annum through a dedicated long term supply of energy to promote the further economic development of Thailand.