SINGAPORE- China's diesel exports in December slumped to 330,000 tonnes, the lowest monthly level since March 2015, amid diminishing export quotas and as refiners curbed runs in response to a slowdown in domestic demand, data showed on Tuesday.

December exports compared with 600,000 tonnes in November and were down 78% on the year, data from the General Administration of Customs showed.

For the whole of 2021, exports of diesel fell 13% to 17.21 million tonnes, the lowest since 2016.

Total refined fuel, including diesel, gasoline, aviation fuel and low-sulphur fuel oil, fell 45% on year to 3.23 million tonnes last month, the lowest monthly level since July 2020.

A diesel crunch triggered by power rationing in the third quarter proved short-lived and the domestic market flipped back into a surplus, analysts said, as reflected in national refinery output, which fell last month by nearly 5% from November and 2% from a year earlier.

Gasoline exports were 940,000 tonnes, rising from November's 810,000 tonnes but down 35% from the same period last year. Annual exports fell 9% to 14.54 million tonnes.

December jet fuel exports were 590,000 tonnes, down from November's 940,000 tonnes.

Rigid border controls and expanding lockdowns in parts of the country to contain a resurgence of coronavirus and pre-empt the highly contagious Omicron variant dampened demand for gasoline and jet fuel.

China's annual refined fuel exports dropped 2.4% over 2020 to 60.31 million tonnes, in the first decline since at least 2015, as the government tightened export quotas to discourage excessive domestic refinery production.

(Reporting by Chen Aizhu; Editing by Jacqueline Wong) ((; Reuters Messaging: