Additional Information - Product Quality Improvement Project

-Translation- 1000/166/2005 August 29, 2005 Subject : Additional Information of the Product Quality Improvement Project Attention: President of the Stock Exchange of Thailand The Board of Directors Meeting of The Bangchak Petroleum Public Company Limited No. 9/2005, held on 29th August 2005, has passed the resolutions about the Extraordinary General Meeting for the approval of the increment of the Company's registered capital by 664,500,000 shares to invest in the Product Quality Improvement Project. A part of such capital increment is for the issuance and offering of the Company's common shares and convertible debentures for the PTT Public Company Limited (PTT) by USD 100 - 120 million. Such transactions will increase the shareholding percentage of PTT to more than 25% but less than 30% of the registered and paid up capital; consequently, PTT will have the management participation to create value additions for the Company. Another part of the capital increment is for the issuance and offering of the Company's common shares for financial investors by approximately USD 30 million. Moreover, the Company also acquires a certain amount of project loans from the commercial banks to support this project. The Company would like to inform that there are some uncertain factors in the implementation of the Product Quality Improvement Project, since the success of the project is still subject to many factors such as final project costs, the results of the Company's due diligence by PTT, as well as, the potential lenders, and a consent of the existing lender for making an investment. Please be informed accordingly. Yours sincerely, -signed- (Patiparn Sukorndhaman) Senior Executive Vice President Accounting and Finance Corporate Planning and Investor Relation Office Tel: 02-335-4583