Did the Ukraine give up its arsenal of nuclear weapons to Russia or was that Belarus?
It was the Ukraine, here's a clipping from an article on the 'liquidation' of the last RS-22. If I get the time, I'll try to find the original post about this, from 2001 or so.
On the books and officially, Ukraine turned over all nukes and all TU-95 and TU-160 bombers and all ICBM subs during the early 90s, perhaps into the mid 90s. The key operative here, of course, is, "officially."