The Trump administration's imposing of 10 percent tariffs effective Sept. 24 was below the 25-percent rate the market had anticipated, and China's response also was less severe than expected, easing worries the trade dispute would crimp global demand. Tariffs are to rise to 25 percent by the end of 2018.

US crude's discount to Brent <WTCLc1-LCOc1> contracted by four cents to $9.33 per barrel on Tuesday after it had mostly widened from around $5 per barrel since early August.

The Brent/WTI spread reached a more than minus $10 per barrel last week, strengthening demand for exports of comparatively cheaper US crude.