China's largest crude oil producer, Bohai Oilfield, has exceeded 90,000 tonnes of daily crude oil production since January, marking the first time the oilfield has surpassed this benchmark, its operator said.

"This is equivalent to one-sixth of the country's daily crude oil production and a new record in the history of the Bohai Oilfield," said Zheng Xu, deputy manager of the production department of the Tianjin branch of CNOOC China Limited.

Compared to the 30-plus tonnes produced in 1967, the daily crude oil production of the oilfield has increased by nearly 3,000-fold.

The breakthrough is just a new starting point for the Bohai Oilfield, and it is expected to hit the daily output peak in October, Zheng said.

In the next two years, oil and gas production in the oilfield will continue to grow and is likely to hit 100,000 tonnes per day, Zheng added.