That's not a "civil war"; Ukraine has been invaded by a foreign army.
"In response to the deteriorating situation in the Donbas, Russia abandoned its hybrid approach, and began a conventional invasion of the region. The first sign of this invasion was 25 August 2014 capture of a group of Russian paratroopers on active service in Ukrainian territory by the Ukrainian security service (SBU)."
https://en.wikipedia.org/wiki/Russo-Ukrainian_War#:~:text=In....