China has various options at its disposal, beyond tariffs, in the power struggle with the United States.Read more
Meanwhile, in China, the amount of crude oil being sent to the country's refineries rose in April to match a previous record.
This is after growing production at private refiners including a big new facility in the country's northeast.
Refinery processing climbed 5% from the year before to 52.1 million tonnes, or 12.68 million barrels per day (bpd), the National Bureau of Statistics said.
The increased refining stands in contrast to slower-than-expected growth in China's industrial output last month.
And oil producing countries are increasingly looking to export refined products to offset domestic gluts.
PetroChina shipped petrol from domestic refiners to Nigeria for the first time in the first quarter.