Baltic states synchronization with CESA
The three Baltic states (Lithuania, Latvia, and Estonia) undertook the synchronization of their electric power transmission infrastructure with the Continental Europe Synchronous Area (CESA), a project known as Baltic Synchro. Managed by ENTSO-E, this initiative aimed to disconnect from the IPS/UPS system, previously governed by the 2001 BRELL Agreement with Belarus and Russia.
Source: Wikipedia — Baltic states synchronization with CESA (CC BY-SA 4.0)