I do not know whether Ukraine will be able to return Crimea, but I believe that it will be able to return Donetsk and Luhansk, Polish President Duda has said

At the same time, the head of state noted that even if the Russians manage to keep at least some Ukrainian territories, it will be a victory for them. 

At the same time, the head of state noted that even if the Russians manage to keep at least some Ukrainian territories, it will be a victory for them. 

“And then the possibility of a new attack from Russia will be very high.”