Bulgaria has joined Slovakia, Hungary and the Czech Republic in seeking to be exempt from a ban on Russian oil imports, diplomatic sources told dpa, after the European Commission unveiled the plans on Wednesday. Representatives from the 27 EU member states examined the proposals – a further punishment for Russia for its invasion of Ukraine – in Brussels on Wednesday. “Let us be clear, it will not be easy. Some member states are strongly dependent on Russian oil. But we simply have to work on it,” EU Commission President Ursula von der Leyen told the European Parliament in Strasbourg. The new s…