The EU wants to vastly reduce Russian gas imports this year, a top official said Tuesday, as political pressure mounts to sever Russia’s main economic lifeline over its invasion of Ukraine. The European Commission, the EU’s executive arm, announced the goal as the United States was expected to impose an oil import ban on Russia in a step considered too far for the Europeans, who fear that the economic consequences would be too severe. Instead, the commission said it could erase a huge share of its dependency on Russia by tapping new gas supplies, ramping up reserves for next winter and acceler…