The three Baltic states disconnected their electricity systems from Russia's power grid on Saturday, the region's operators said, part of a plan designed to integrate the countries more closely with the European Union and boost security.

More than 30 years after leaving the Soviet Union, Estonia, Latvia, and Lithuania will join the EU's grid.

After years of preparation, Lithuania, Estonia and Latvia will disconnect from their Russian-controlled electricity grid this weekend, erasing one of the last traces of their Soviet past. CNN’s Clare Sebastian explains the security concerns,