Russia has not achieved any of its goals in Ukraine, within so-called “special military operation”. That was announced by russian President's chief spokesman Dmitry Peskov in an interview with CNN.
When asked what Putin had achieved in Ukraine so far, Peskov answered: "He hasn't achieved yet.". He also claimed that the invasion of Ukraine was "going on strictly in accordance with the plans and the purposes that were established beforehand."
When asked under what conditions Russia would use its nuclear weapons, Peskov replied, "if it is an existential threat for our country, then it can be."