Top officials from the Baltic states -- Estonia, Latvia, and Lithuania -- as well as Polish and Swedish officials are inaugurating two electrical links binding Lithuania with the West.
The move at the Palace of the Grand Dukes in the Lithuanian capital, Vilnius, on December 14 is being lauded as a key to reducing the region's energy dependence on Russia.
Although EU and NATO members since 2004, the Baltic states are still part of a Russian-controlled power ring.
The future plan by EU and Baltic officials is to fully synchronize the three countries' energy systems with the continental European grid.
Russia has been accused of using its energy-supplying capacities to put political pressure on its neighbors.
Moscow has also expressed concerns that the EU-Baltic energy integration would make its European exclave, Kaliningrad, energy dependent on the West.
Recent cuts in electricity supplies to Crimea -- annexed by Russia from Ukraine last year -- have made Moscow even more concerned over the Baltic states' efforts to get energy from the West.