Report on the last Exercise of Warratns (STEC-W2 No.12/2008)

Ref: ST/010/2008/0027 April 18 th, 2008 Re: Report on the last Exercise of Warrants (STEC-W2 No.12/2008) To: The President The Stock Exchange of Thailand Sino-Thai Engineering & Construction Public Company Limited would like to report on the exercise of STEC-W2 No.12 on April 18th, 2008. There is none of STEC-W2 holder exercise the warrants. Therefore, the remaining warrants listed in the Stock Exchange of Thailand are 163,548,461 units. STEC-W2 expired and could not be used since April 21st, 2008. Please be informed accordingly. Yours sincerely, Mr. Woraphant Chontong SEVP. Financial and Administration Division