Chinese oil firm in biggest takeover (2)

The Committee on Foreign Investment in the US approved the deal earlier this month, clearing the last major hurdle for the acquisition to succeed.

Nexen will operate as a wholly owned subsidiary of CNOOC and will continue to be led by its CEO, Kevin Reinhart, who has been with Nexen for over 18 years. Li Fanrong, CNOOC's chief executive, will be Nexen's chairman.

CNOOC has promised to keep Nexen's headquarters in Calgary and also make it the headquarters of the Chinese company's North and Central American assets.

Nexen, which reported a net loss in the fourth quarter of 2012, will be delisted.

Wang Zhen, a professor with the China University of Petroleum, told Xinhua the takeover was just the first step, as the company would face many challenges on the road ahead.

Increasing the company's value was an important target of the acquisition, which means CNOOC will need to boost its business management capabilities, Wang said.

As environmental awareness expands worldwide, CNOOC should also shoulder its due social responsibilities in its global operations, Wang said.

He said the company will also face challenges in global business management, as it has to resolve differences in financial affairs, business practices and culture.