Saudi Arabia was China’s biggest crude oil supplier in June for the eighth consecutive month, customs data showed on Tuesday, while shipments from United Arab Emirates and Kuwait fell further, possibly signalling slower imports of Iranian oil.

Arrivals of Saudi Arabian crude oil reached 7.2 million tonnes last month, equivalent to 1.75 million barrels per day (bpd), according to data from the General Administration of Customs in China.

Shipments from Russia were 6.65 million tonnes, or 1.62 million bpd.

China slowed crude oil purchases in the second quarter amid rising global oil prices and shrinking refining margins. Its imports in the first half fell for the first time year-on-year since 2013.

Spot premiums for Russian ESPO crude, a China-focused grade, dropped to the lowest since April following muted demand from Chinese independent refiners whose buying appetite was cooled by factors including crude oil import quotas, government investigations, and high oil prices.

The customs data also showed that China’s imports of crude oil from the UAE and Kuwait fell 32% and 23% respectively last month from a year ago.

Reuters has reported that Iran has sold record amounts of oil since late 2020, disguised as crude oil from other origins that included the UAE.

Meanwhile, imports from Malaysia in June doubled last year’s level to 1.17 million tonnes despite Beijing’s recent tax reform on bitumen blend which would dent demand for the fuel imports.

The official data recorded zero arrivals from Iran and Venezuela.