Oil futures ticked slightly lower early Tuesday, a day after a fresh round of U.S. sanctions aimed at curtailing Iran’s crude exports provided a modest lift.

Oil prices rose for a second day on Tuesday as the U.S. imposed fresh sanctions on Middle Eastern producer Iran that increased concerns supply might tighten.

Oil prices were rising, with Brent crude advancing 0.4% to $74.36 a barrel and WTI up 0.2% at $70.85 a barrel. Crude has fluctuated in the mid-$70s for Brent and low $70s for WTI over the past week, Goldman Sachs analysts said in a note.