China National Offshore Oil Corporation (CNOOC) has announced commencement of production at the Buzios5 well.

The project is the fifth phase of the Buzios oilfield, which is in the Santos Basin off the coast of Brazil at a water depth of up to 2,200 metres.

CNOOC Petroleum Brasil, a wholly owned subsidiary of the Chinese energy company, has a 7.34% interest in the Buzios project.

As the operator, Brazilian state-owned Petrobras holds 88.99%, and CNODC Brasil Petróleo e Gás Ltda holds a 3.67% stake in the oilfield.

Buzios is claimed to be the largest deep-water pre-salt oilfield in the world, with a current production capacity of about 600,000 barrels of oil equivalent per day.

The project will be developed using a floating production, storage, and offloading (FPSO) and subsea production system. Five producing wells and five injectors have already been drilled.

Up to 150,000 barrels of crude oil, six million cubic metres of natural gas, and 220,000 barrels of water per day are expected to be produced by these wells.

CNOOC president Xia Qinglong said: "Buzios5 is the first project to commence production after CNOOC joined the Buzios project, which will inject new momentum into our overseas production growth.

“We adhere to win-win cooperation with the host government and partners, to jointly develop the world-class ultra-deepwater project, and to contribute to the sustainable development of Brazil's oil and gas industry, economy and society."

Last year, CNOOC paid $1.9bn to Petrobras to increase its stake in the production sharing agreement at the Buzios oil field.