CNOOC, Nexen Agree to Extend 'Outside Date' of Arrangement Agreement to March 2, 2013

Nexen

announced today that CNOOC

and Nexen have mutually agreed to extend the "Outside Date" of the Arrangement Agreement by 30 days to March 2, 2013. The Outside Date was originally January 31, 2013. Either party may, except in certain circumstances, extend the Outside Date from time to time if the required regulatory approvals have not been obtained, provided that in aggregate such extensions shall not exceed 75 business days from January 31, 2013. In connection with the extension, Nexen also announced that it will postpone the release of its 2012 fourth quarter and annual operating and financial results. Completion of the Agreement remains subject to the receipt of United States regulatory approval and the satisfaction or waiver of other customary closing conditions. Key regulatory approvals have been received from Canada, the United Kingdom, the European Union and the People's Republic of China. About Nexen Nexen Inc. is a Canadian-based global energy company, listed on the Toronto and New York stock exchanges under the symbol NXY. Nexen is focused on three growth strategies: oil sands and shale gas in western Canada and conventional exploration and development primarily in the North Sea, offshore