BRUSSELS — The European Union unveiled a new package of proposed sanctions against Russia on Tuesday, targeting the country’s banking, energy and trade sectors in an effort to weaken its economy. European Commission President Ursula von der Leyen said Russia’s economy was "slowing sharply" as she presented the bloc’s 21st sanctions package, seven weeks after Council President António Costa announced the previous one entering into force . "Four years after the start of its full-scale invasion,