BP and China National Petroleum Corp. (CNPC) might split their joint venture 50-50 to develop Iraq's Rumaila oil field, said Christof H. Ruehl, BP's vice president and chief economist.

But a senior manager in charge of CNPC's international business told Caijing the companies have yet to agree on the share arrangement.

The field in southern Iraq is estimated to have reserves of 17.7 billion barrels.

BP and CNPC are obliged to increase output at Rumaila from the current 1.1 million barrels per day to 2.85 million bpd within six years