A Russian claim based on zero evidence. The OSCE, on the other hand, has documented Russian ceasefire violations since 2015 and the trafficking of 30,000+ Russian soldiers coming and going from the Donbass alongside Russian supply columns. Russia was even using long range artillery in the Donbass to train their conscripts because they knew Ukraine's hands were tied for serious retaliation.
What is clear is no one will change anyone’s mind. My belief is the “ last chapter”. Time will most certainly tell.
Ukraine 1991-2023.