The parliament also called for guarantees of the memorandum signed by Ukraine, Britain, Russia and the United States in Budapest in 1994. That agreement guaranteed Ukraine’s sovereignty and current borders in exchange for surrendering the nuclear weapons that were left after the collapse of the Soviet Union.
It appears Russia is saying the Ukraine governmnet is not legitimate so the treaty is void.
Really doesn’t matter what other countries say/do if the Ukrainian military isn’t willing to fight a big war with Putin right now.
The Ukraine government is legitimate and the treaty isn't void.