China's biggest privately owned bunker supplier Brightoil Petroleum is expanding further into the upstream oil business as it diversifies away from the fickle fuel trading and shipping market.

The strategy it is using is to take over established fields and exploit them.

The company said is negotiating to buy the oil production assets of several foreign companies as they exit the business after losing operational control. This opportunity has arisen as production sharing contracts signed with foreign partners are expiring.At a shareholders' meeting Brightoil's $8.4bn acquisition of minority stakes in two mature fields from Anadarko Petroleum were approved.

New chief executive, Bruce Yung revealed of the other discussions some were preliminary, while one was more advanced.Brightoil founder Sit Kwong-lam resigned as chief executive but remains its chairman and majority shareholder.