Indeed. There was even a question of whether they could legally be considered Ukrainian or Russian weapons, regardless of where the command centre was. To solve that while the talks were ongoing they set up a ‘joint’ command centre in Moscow with ex-SSR countries theoretically sharing joint control over the weapons with Moscow.
Ukraine at one point wanted to formally claim ownership over the weapons, as after all breaking the permissive action locks wasn’t that difficult. The US talked them out of it, as a lead up to the Budapest Memorandum.
We all know how much the security guarantees of that agreement were worth.
