| 1.   | I                  have reviewed this annual report on Form 20-F of CNOOC Limited                  as amended                  by Amendment No. 1 thereto; |
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| 2.   | Based                  on my knowledge, this report does not contain any untrue statement                  of a                  material fact or omit to state a material fact necessary to make                  the                  statements made, in light of the circumstances under which such                  statements                  were made, not misleading with respect to the period covered by                  this                  report; |
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| 3.   | Based                  on my knowledge, the financial statements, and other financial                  information                  included in this report, fairly present in all material respects                  the                  financial condition, results of operations and cash flows of the                  company                  as of, and for, the periods presented in this                  report; |
|----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 4.   | The                  company’s other certifying officer(s) and I are responsible for                  establishing and maintaining disclosure controls and procedures                  (as                  defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the                  company and                  have: |
|----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (a)   | Designed                  such disclosure controls and procedures, or caused such disclosure                  controls and procedures to be designed under our supervision, to                  ensure                  that material information relating to the company, including its                  consolidated subsidiaries, is made known to us by others within                  those                  entities, particularly during the period in which this report is                  being                  prepared; |
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| (b)   | [*Paragraph                  omitted pursuant to SEC Release Nos. 33-8238 and                  34-47986*] |
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| (c)   | Evaluated                  the effectiveness of the company’s disclosure controls and procedures and                  presented in this report our conclusions about the effectiveness                  of the                  disclosure controls and procedures, as of the end of the period                  covered by                  this report based on such evaluation;                  and |
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| (d)   | Disclosed                  in this report any change in the company’s internal control over financial                  reporting that occurred during the period covered by the annual                  report                  that has materially affected, or is reasonably likely to materially                  affect, the company’s internal control over financial reporting;                  and |
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| 5.   | The                  company’s other certifying officer(s) and I have disclosed, based on our                  most recent evaluation of internal control over financial reporting,                  to                  the company’s auditors and the audit committee of the company’s board of                  directors (or persons performing the equivalent                  functions): |
|----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| (a)   | All                  significant deficiencies and material weaknesses in the design                  or                  operation of internal control over financial reporting which are                  reasonably likely to adversely affect the company’s ability to record,                  process, summarize and report financial information;                  and |
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| (b)   | Any                  fraud, whether or not material, that involves management or other                  employees who have a significant role in the company’s internal control                  over financial reporting. |
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| By:    | /s/                    Chengyu Fu |                                                    |
|--------|-----------------------------------|---------------------------------------------------------|
|   | Name:                             | Chengyu                    Fu                           |   |
|   | Title:                            | Chairman                    and Chief Executive Officer |   |
|   |                              |                                                    |   |

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