CNBC | Oil firm as OPEC, Russia resist calls to raise output as Iran sanctions loom CNBC Oil markets opened strongly on Tuesday, with Brent crude remaining near a four-year high reached in the previous session. Oil markets have been driven up by looming U.S. sanctions against Iran and an unwillingness or inability by Middle East dominated ... Supply concerns push oil settles higher OPEC Is the Oil Producer of an Unlikely Future Global oil ends at a nearly 4-year high as producers rebuff Trump's demand to keep crude prices low |