According to Rose Gottemoeller, Under Secretary of State for Arms Control and International Security, ‘Nuclear weapons don’t buy security. They provide instability and disaster’.
Here is the comparison of nuclear arsenals of Ukraine and Russia as of 1991.
In 1994 Ukraine prohibited use and production of nuclear weapons on the territory of the country.
Since then Ukraine got rid of all nuclear arsenal.
On the contrary, Russian Federation strengthened its nuclear arsenal.