HARBIN - Daqing Oilfield, the largest oilfield explored by China's major oil and gas producer PetroChina, produced 40 million tons of crude oil in 2014, the company announced on Wednesday.

This is the twelveth consecutive year that the oilfield yielded more than 40 million tons.

It also produced 3.5 billion cubic meters of natural gas.

Previously, the oil field had an annual output exceeding 50 million tons crude oil for 27 consecutive years, but output shrank due to harder operations in oil exploitation.

According to the economic working conference of northeast China's Heilongjiang province on Saturday, Daqing Oilfield, which produces nearly a quarter of China's total oil output, will reduce production by 1.5 million tons next year.

By 2020, Daqing's annual oil output will fall to 32 million tons, the conference said.

As China's largest inland oilfield, Daqing has produced more than 500 million tons of crude oil in the past 12 years.

Discovered in 1959, Daqing is located in northeast China's Heilongjiang province.