I suspect they had the knowledge, considering Ukraine was where one of their early nuclear research facilities were - they were able to reproduce early fission

I suspect they had the knowledge, considering Ukraine was where one of their early nuclear research facilities were - they were able to reproduce early fission experiments and made a proposal to leverage the ability in bombs in 1940 but were dismissed by nuclear experts in Moscow[0]. And it was Ukrainian's who worked to reverse engineer the V2 rockets post WWII and turned it into the rocket design that put Sputnik into space[1]. [0] - https://www.wilsoncenter.org/publication/ukraine-and-soviet-nuclear-history https://www.wilsoncenter.org/publication/ukraine-and-soviet-... [1] - https://euromaidanpress.com/2021/07/26/how-ukraine-wants-to-make-its-space-industry-great-again/ https://euromaidanpress.com/2021/07/26/how-ukraine-wants-to-...