Hungary and Slovakia are in a heated clash with Ukraine over a new ban on Russian oil that they fear will disrupt their energy supplies. The EU is stepping in to mediate, as Budapest and Bratislava warn that Ukraine's move could severely impact their oil imports. Hungary is even threatening to block EU funds meant for military aid to Ukraine in protest. With the EU examining the situation closely, the conflict underscores growing tensions over energy security and political maneuvering within the bloc.

On Tuesday, the European Union announced that it would intervene after Slovakia and Hungary claimed that Ukraine's partial restriction on Russian crude exports through the nation posed a threat to their oil supplies.

Last month, Kyiv imposed sanctions that prevented pipeline crude exported to Central Europe by Lukoil, the biggest private oil company in Moscow, raising concerns about supply shortages in Bratislava and Budapest.

Hungary and Slovakia claimed the move broke a 20...