The military junta which seized control of the African nation of Niger, declared the Ambassador to France as "persona non grata" the original Latin term for Unwanted person. In Diplomatic Circles, that is how a country ejects an unwanted Ambassador from its land. Except the French Ambassador REFUSES to leave!
The Ambassador says that the military junta is not the legitimate government of Niger and so it does not have the authority to declare him persona non grata. As such, he refuses to leave!
Now, this gets interesting. A foreign Embassy is protected by Diplomatic Treaties and is the sovereign territory of the country it represents, in this case, France.
If Niger were to use military or police force to enter that Embassy and physically eject the Ambassador, THAT would be a Casus beli (cause for war).
So what did the military junta of Niger do? They cut-off the embassy electric and water supplies!
This ought to get interesting, fast, now that Embassy staff can't flush toilets, take showers, make coffee, etc.