Nexen Inc's shareholders have approved CNOOC Ltd's US$15.1 billion bid for the Canadian oil and natural gas producer, the biggest foreign takeover by a Chinese company.

About 99 percent of common shareholders who voted cast ballots in favor of the takeover, S. Barry Jackson, non-executive chairman of Nexen, said in Calgary yesterday. The deal needed the approval from two-thirds of shareholders.

CNOOC, China's largest offshore oil and gas producer, agreed to pay US$27.50 a share for Nexen in an offer announced on July 23. The deal still needs approval from the Canadian government, which reviews foreign acquisitions worth more than C$330 million (US$337 million) to ensure there's a "net benefit" to the country.

There's "low risk" Canada will block the deal or impose onerous conditions, said Philip Skolnick, analyst at Canaccord Genuity Corp in New York.