China's imports from Saudi Arabia fell 21 percent in May from a year earlier but retained their top ranking among suppliers for a ninth month in a row, customs data showed.
Shipments from Saudi Arabia were 7.2 million tonnes last month, or 1.69 million barrels per day (bpd), data from the General Administration of Chinese Customs showed.
That compared to 6.47 million tonnes in April and 9.16 million in May 2020.
Imports from second-largest supplier Russia also dropped from a month earlier, to 5.44 million tonnes, or 1.28 million bpd.
The scale-backs by the top two exporters were in line with a steep annual decline of nearly 15 percent to this year's lowest total crude imports into China.
Imports from United Arab Emirates arrivals fell 25 percent last month from year-ago levels.
That is a possible sign that Iranian oil shipments were slowing further from peaks early this year amid talks between Tehran and world powers to revive the nuclear deal the United States exited in 2018.
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 and Oman.
Customs recorded zero imports from Iran for a fifth month in a row.
The customs' database also showed a 3.6 percent year-on-year rise to 1.04 million tonnes of imports from Malaysia, which traders said has been a key transshipment point for heavy crude blends from Venezuela.
Official data has consistently recorded zero imports from Caracas since October 2019, as dominant state importer CNPC halted loading, fearful of US sanctions.
Venezuela oil, however, had slipped into China, passed on as Malaysian bitumen blend after transshipments in Malaysian waters, analysts said.
Imports from the United States reached 1.07 million tonnes, nearly doubled the level a year earlier.