EU leaders have agreed to cut Russian oil imports by 90% by the end of the year. The agreement is already reached, with only the details to be clarified.According to Reuters, about 65% of Russian oil exports to the European Union are delivered to the continent by tankers, with the rest coming through the Druzhba pipeline.Poland and Germany had already committed to end Russian crude imports via the Druzhba pipeline by the end of the year, raising the ban coverage to around 90%. First and foremost, the embargo will affect tanker traffic. This will be a problem for those EU members who receive Russian oil in this way. At the moment there is no clarity on how these EU members will be compensated.Meanwhile, Hungary, the Czech Republic and Slovakia will be exempted from the embargo, leaving 10% of usual Russian oil flows in place. There was no mention of Bulgaria in the Reuters report, but the southern European state was also part of the group of countries opposing any embargo that could threaten the security of its oil supply.The European Commission proposed a full oil embargo against Russia in early May as part of its latest sanction package. Hungary, however, immediately and quite vocally opposed it, arguing it would need hundreds of millions of dollars to transform its pipeline and refinery industry. The Central European state relies on Russia for more than 80% of its oil.The following weeks saw active discussions as more EU members heavily reliant on Russian oil followed Hungary's example, with Bulgaria threatening a veto on any embargo proposal unless it received an extension to reduce and eventually eliminate Russian oil imports.Following the news of the embargo agreement, Brent crude was trading at $122.63 per barrel: