The EU's move followed the complete shutdown on Wednesday of Russian gas shipments through Ukraine to the EU, a step that caused the disruption of gas supplies to reach alarming proportions in EU countries almost wholly dependent on Russian gas such as Bulgaria and Slovakia.
EU leaders hope to seal a deal at emergency talks in Brussels that will bring together Alexei Miller and Oleh Dubyna, the chairmen of Gazprom and Naftogaz, the Russian and Ukrainian gas companies, as well as senior EU policymakers.
It marks the first attempt by the EU to use its weight as Russia's largest energy customer, and its influence as a club of prosperous democracies which Ukraine has strong aspirations to join, to end the sudden crisis over interrupted gas supplies.