Oil from Russia bound for Hungary and Slovakia , via the Druzhba pipeline  that first goes through Belarus and Ukraine, started flowing again on Wednesday after an interruption lasting months.  The stoppage had been a source of severe tension between Ukraine and Hungary and Slovakia , which intensified amid the added strain on energy prices caused by the war in Iran and the wider Middle East .  Restarting supplies should also unlock a massive €90 billion EU loan for Ukraine originally agreed in December, which Hungary and Slovakia had held up at the most recent EU leaders' summit because of the halt in oil supplies.  Landlocked Hungary and Slovakia are exempt from EU sanctions on Russian oil deliveries imposed since the full-scale invasion of Ukraine  because of their pronounced dependence on Moscow as a supplier.  US waiver boosts Russian oil revenues amid Iran war To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video…