BEIJING- China's national offshore oil and gas producer CNOOC Ltd reported on Thursday its first quarter revenue surged 21% on year on recovering oil and gas prices and higher sales.

Revenue was 48.34 billion yuan ($7.45 billion) over the January-March period. Realised oil prices rose 20.5% to $59.07 per barrel, while gas prices were up 5% on year at $6.71 per thousand cubic feet.

Total net production during the period reached 137.7 million barrels of oil equivalent (boe), up 4.7% from the same period last year, with domestic output nearly 9% higher than a year earlier.

Production from overseas oilfields dropped 3.2% over the period, owing to lower output at the Egina project in Nigeria, Eagle Ford in the United States and Buzzard in Britain.

A fire accident at CNOOC's offshore production platform in Bohai Bay in early April left three staff members missing. The firm estimated a loss of up to 600,000 barrels of output, representing 0.1% of annual production scheduled in 2021.

CNOOC aims to raise production to 545-555 million barrels of oil equivalent (boe) this year from 528 million boe in 2020.

Its capital spending in the past three months dropped 5.1% on year to 16.04 billion yuan, it said.

($1 = 6.4923 Chinese yuan renminbi)

(Reporting by Muyu Xu in Beijing and Chen Aizhu in Singapore; editing by David Evans) ((muyu.xu@thomsonreuters.com; +86 10 56692117;))