China National Offshore Oil Corp. is working to control costs in its 2015 development plan in response to falling oil prices, its financial officer said.

CNOOC said in its fourth quarter report it was cutting its capital expenditure budget by around 30 percent from last year to around $12 billion, with development expenses taking the biggest hit.

"In response to challenges from falling oil prices, we will control our costs and strive for the effective implementation of our capital expenditure plan in order to improve the overall performance of the company," Chief Financial Officer Zhong Hua said in a statement Tuesday.

The company in late 2014 put 33 blocks totaling 48,691 square miles on the auction block. CNOOC tried last year to reverse sagging production from mature fields. During the first half of 2013, production from the Bohai Bay, which accounts for more than half of all Chinese production, declined 2.5 percent from the previous year to 411,000 barrels of oil equivalent per day.

Net production for 2015 is estimated to range between 475 million to 495 million barrels of oil equivalent, with Chinese production accounting for around 67 percent of the output. Net production for 2016 is expected at 509 million boe and 513 million boe for 2017.

The company said it expects to meet its annual targets by "cost control and efficiency enhancement" efforts.

CNOOC said it estimated net production for 2014 was around 432 million boe.