London-based Royal Dutch Shell Plc (NYSE: RDS-A, RDS-B) entered into an irrevocable, non-discretionary arrangement with an independent third party to enable the purchase of 'B' ordinary shares, for cancellation, during its 1Q 2013 results closed period.

The close period begins on April 2 and is up to and including May 2.

The purpose of the share buyback program is to offset dilution created by the issuance of shares for the company's scrip dividend program. At this time, it is less economic for the company to purchase 'A' ordinary shares under the share buyback program due to Dutch dividend withholding tax rules.

Any purchases will be affected within certain pre-set parameters and in accordance with the company's general authority to repurchase shares and chapter 12 of the listing rules.