At one point, I read through the NATO articles. There was plenty of detail on how a new nation might join - but I saw nothing on how an existing member might be ejected. Have you read these? It might be that there isn't a way to eject a member nation (including Hungary) from NATO.
No idea on the EU.
Written by Bob Koure
Retired software architect, statistical analyst, hotel mgr, bike racer, distance swimmer. Photographer. Amateur historian. Avid reader. Home cook. Never-FBer