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Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement , make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement . JOOC CNOOC Limited ( 中國 海洋 石油 有限公司 ) ( Incorporated in Hong Kong with limited liability under the Companies Ordinance ) ( Stock Code : 00883 ) ANNOUNCEMENT The Board hereby announces certain selected unaudited key operational statistics of the Group for the first quarter of 2021 ( ended 31 March 2021 ) . The comparative statistics of the Group for the first quarter of 2020 ( ended 31 March 2020 ) are also disclosed in this announcement . The board of directors of CNOOC Limited ( the “ Company ” ) ( the " Board " ) hereby announces certain selected unaudited key operational statistics of the Company and its subsidiaries ( together the " Group " ) for the first quarter of 2021 ( ended 31 March 2021 ) . The comparative statistics of the Group for the first quarter of 2020 ( ended 31 March 2020 ) are also disclosed in this announcement . The Company achieved a total net production of 137.7 million barrels of oil equivalent ( “ BOE ” ) for the first quarter of 2021 , representing an increase of 4.7 % year over year ( " YoY " ) . Production from China increased by 8.7 % YoY to 94.7 million BOE , mainly attributable to production growth from the commencement of new projects including Liuhua 16-2 / 20-2 and Luda 16-3 / 21-2 ; Overseas production decreased by 3.2 % YoY to 43.0 million BOE , mainly due to the decreased production from Egina project in Nigeria , Eagle Ford project in the U.S. and Buzzard oilfield in the U.K. North Sea . For the first quarter of 2021 , the Company made two new discoveries and drilled 18 successful appraisal wells . In offshore China , Kenli 10-2 and Wenchang 9-7 oil and gas bearing structures were successfully appraised . Kenli 10-2 is expected to become a mid - to - large sized oilfield , which indicates broad exploration prospects for shallow lithology oil and gas reservoirs in Bohai , while Wenchang 9-7 is expected to become a mid - sized oilfield . For the new projects planned to commence production this year , Caofeidian 6-4 oilfield has commenced production and other projects progressed as scheduled . The unaudited oil and gas sales revenue of the Company reached approximately RMB 48.34 billion for the first quarter of 2021 , representing an increase of 21.0 % YoY , mainly due to the combined effect of rising international oil price and increased oil and gas sales volume . During the quarter , the Company's average realised oil price increased by 20.5 % YoY to US $ 59.07 per barrel , which was in line with the trend of international oil prices . The Company's average realised gas price was US $ 6.71 per thousand cubic feet , representing an increase of 5.3 % YoY , primarily due to the higher gas price in North America . For the first quarter of 2021 , the Company's capital expenditure decreased by 5.1 % YoY to approximately RMB 16.04 billion as a result of the schedule of development projects . 1