The European Union (EU), eager to distance itself from the Kremlin following its invasion of Ukraine, proposed Wednesday an embargo on Russian crude within six months. The measure, anticipated for weeks, would also cut off refined oil products from Russia by the end of 2022.

EU members were debating the proposal Wednesday. It would follow a U.S. ban on Russian oil and gas imposed by the Biden administration in the early days of the war. Russia launched the assault on its eastern European neighbor in late February.

The news sent already lofty oil prices surging Wednesday. West Texas Intermediate and Brent crude prices both climbed more than 4% in early trading, rising higher above the $100/bbl threshold.

Western sanctions against the Kremlin in protest of the war, including...