CNOOC Ltd. has closed a $4 billion multi-tranche bond. Proceeds from CNOOC's bond issue, which was closed May 3, 2013, will be used to repay a portion of its $6 billion bridge loan. The deal was divided into a $750 million three-year tranche, a $750 million five-year tranche, a $2 billion 10-year tranche and a $500 million 30-year tranche.

CNOOC Ltd. announce its operational results for the first quarter of 2013. During the quarter, the company achieved a total net production of 93.6 million barrels of oil equivalent (BOE), representing 17.3% increase year over year (YoY), primarily attributable to the production contribution from the acquisition of Nexen Inc. ("Nexen"), the new oil and gas projects on stream, the resumption of Penglai 19-3 oil field and the overseas projects. For the first quarter, the company made four new discoveries and six successful appraisal wells in offshore China. The appraisal confirmed that Penglai 15-2 was a mid to large sized crude oil discovery. In the perspective of overseas development, the company successfully completed the acquisition of Nexen. During the period, the company's capital expenditure for exploration, development and production reached approximately RMB 14.80 billion, representing an increase of 53.5% YoY.

CNOOC Ltd. announced that Weizhou 6-12 oil field has commenced production. Weizhou 6-12 oil field is located in Beibu Gulf Basin in the north part of the South China Sea with an average water depth of about 29.2 meters. The project has 10 producing wells and is expected to hit its peak production in 2013. The company holds 51% interest and acts as the Operator of Weizhou 6-12 oil field. The partners of this oil field are Roc Oil (China) Company, Horizon Oil (Beibu) Ltd. (including Petsec Petroleum LLC) and Oil Australia Pty Ltd.