Cnooc, China’s largest offshore oil company, yesterday reported stronger-than-expected production growth for the third quarter, a relief for investors after a year of disappointing output.

The Chinese oil company is in the middle of a $15bn friendly acquisition of Nexen, a Canadian oil group, and chief financial officer Zhong Hua said he expected the deal to be completed by the end of this year. “We assume it will succeed and will make the greatest effort to see it through,” said Mr Zhong.

The acquisition has been approved by shareholders of both companies but is awaiting approval from Canadian regulators, who are expected to make a decision before November 11. Mr Zhong declined to discuss specifics of how the approval process was progressing, noting only that Cnooc was in close communication with regulators in Canada, the US and other countries about the deal.