“They are restricting what enters and leaves their nation, which I thought nations were allowed to do.”
There is a written treaty addressing that. They are abrogating it. The other part of the treaty is that Russia recognized their independence.
> There is a written treaty addressing that. They are abrogating it. The other part of the treaty is that Russia recognized their independence.
aha, this (signed in 1991; cf. esp. art. 14)?
https://treaties.un.org/doc/Publication/UNTS/Volume%201787/volume-1787-I-31051-English.pdf