Released months behind schedule, the quotas totalled 7.5 million tonnes, and were issued to six state-run companies and a private refiner, according to four people familiar with the matter.

That compares with 28 million tonnes in the second batch last year and brings total issues for 2021 to 35.5 million tonnes, 40% lower than 2020.

The quota issues did not give the breakdowns by products, which normally cover diesel, gasoline and aviation fuel. Beijing normally issues several batches of fuel export quotas during a year. For 2020, it allotted a total of nearly 59 million tonnes.

Separately, the government also issued 3 million tonnes of low-sulphur fuel oil (LSFO) export quotas in the latest batch, the sources said.

The Ministry of Commerce, which handles quota releases, did not immediately respond to Reuters' request for comment.

LSFO marine fuel quotas issued so far for 2021 effectively totaled 11 million tonnes, following 5 million tonnes in first batch released in late 2020 and 3 million tonnes around May or June, said two of the sources.

China started levying hefty taxes on imports of light cycle oil (LCO), mixed aromatics and diluted bitumen from June 12, to curb imports that it blames for worsening a fuel surplus and polluting the environment.

The recipients of the latest issues of refined fuel permits are CNPC, Sinopec, CNOOC, Sinochem, China National Aviation Oil Company, defence conglomerate Norinco and private refiner Zhejiang Petrochemical Corp (ZPC), sources said.

LSFO was issued to Sinopec, CNPC and CNOOC only. ZPC, the only private firm awarded the marine fuel quota in the first batch of 2021 was no longer on the list, they said.

(Reporting by Chen Aizhu and Florence Tan in Singapore, Muyu Xu in Beijing, Editing by Louise Heavens, Tomasz Janowski & Simon Cameron-Moore)

By Chen Aizhu and Muyu Xu