Considering Russia denied their intent to invade as they were conducting it, I don’t know that their statements should be considered truth regarding their plans and goals. But here’s Westpoint’s take on the matter:
Initially, the Russian regime may have regarded its invasion of Ukraine as a “regional conflict” with “important” military-political goals, and its classification as a “special military operation” may have been genuine. Indeed, it seems that the Kremlin’s ambitious political objective was to install a new, pro-Russian government in Kyiv by lightning action.