China National Offshore Oil Corporation (CNOOC) declared Monday it has reached an agreement with Canadian energy company Nexen Inc., according to which the expiration date of the Nexen Inc. acquisition will be postponed to March 2 from Jan. 21, 2013.　

In July 2012, the CNOOC announced its bid for Canadian oil and gas company Nexen Inc at 15 billion U.S. dollars. According to the announcement CNOOC made in July, if the transaction haven't been approved by relevant supervision authority, either party has the rights to postpone the expiration date within 75 working days from Jan. 31, 2013.

CNOOC said the purchase of Nexen Inc. is restricted by routine terms of delivery including court approval, approval of more than two-thirds shareholder or deputy at the extraordinary general meeting and permission of government and supervision authority including but not limited to relevant departments in Canada, United States, European Union and China.

Currently, the acquisition has already been approved by Nexen shareholders, local court in Canada, Canadian government, China National Development and Reform Commission. Due to Nexen's oil gas asset in Gulf of Mexico, this purchase should obtain approval of the Committee on Foreign Investment in the U.S. (CFIUS), a U.S. department responsible for foreign-related economic activities.