Chief of Defense Intelligence Kyrylo Budanov said in an interview with the Washington Post that approximately 326,000 Russian soldiers are currently fighting in Ukraine.
According to Budanov, only 9% of Russia’s stock of long-range Kalibr missiles remains. Those numbers can't be independently verified.
Regarding fears that Russia might launch a nuclear strike if Ukraine was to liberate Crimea, Budanov dismissed it as a scare tactic – “Russia is a country that you can expect a lot from but not outright idiocy. Carrying out a nuclear strike will result in not just a military defeat for Russia but the collapse of Russia. And they know this very well.”