-Translation - AIS-CP 040/2006 March 24, 2006 Re: Notification of the Book Closing for Amortizing and Interest Payment of Debentures of the Company (AIS07OA) To: The President The Stock Exchange of Thailand Refer to: The Letter No. MKOT.65-490484 of Siam Commercial Bank on March 21, 2006 Advanced Info Service Public company Limited ("the Company") would like to inform you that the Company will close the registered book for amortizing and interest payment of debentures of the Company (AIS07OA), the details are shown in the referenced letter. Please be informed accordingly. Yours faithfully, -Signed- Pong-Amorn Nimpoonsawat (Mr.) Chief Finance Officer Advanced Info Service Public company Limited Referenced Letter MKOT.65 - 490484 March 21, 2006 Notification of Book Closed Date for Amortizing and Interest Payment Managing Director The Stock Exchange of Thailand With reference to Debentures issued by Advanced Info Service Public Company Limited named The Amortizing Debentures of Advanced Info Service Public Company Limited No. 4/2002 Due 2007 (AIS07OA) with face value of Baht 1,000 and offering amount at 5,000,000 units "the Debentures", the Company will pay amortizing and interest on semi annual basis. Interest shall be payable on 21 April and 21 October of each year throughout the term of the Debentures. The Bank as a capacity of Registrar of the Debentures would like to inform that the second amortizing and the seventh coupon payment is due on 21 April 2006. Amortizing 200 Baht per unit. Coupon rate is 3.65 % per annum. Calculation period is 182 days starting from 21 October 2005 to 20 April 2006. The book closed date of the Debentures is on 7 April 2006 at noon. Please be informed accordingly. Yours faithfully, The Siam Commercial Bank Public Company Limited (Authorized Signatory)