New Delhi, Feb. 25 -- Slovakia on Monday escalated a dispute with Ukraine over oil deliveries by halting emergency electricity supplies to the country suffering from daily blackouts caused by Russia's bombardment of power plants and transmission lines.

Russian oil shipments to Slovakia and Hungary have been interrupted since Jan. 27 after what Ukrainian officials say were Russian drone attacks that damaged the Druzhba pipeline, which carries Russian crude across Ukrainian territory and into Central Europe.

The two most pro-Russian countries in the European Union blamed Ukraine for deliberately holding back the oil shipments. They received a temporary exemption from an EU policy prohibiting imports of Russian oil.

Populist Slovak Prime ...