If you were winning the war during WW2, what could Germany have offered the Russians, the US, and the British to stop the war?  

If Adolf had said, truce. Stop. I want peace now.  Please leave Germany, and I will apologize to the Jews, the Polish, the French.... would US, UK, and Russia have said, "ok."?

Extrapolate that, if Russia is winning the war, what could Ukraine offer to get the Russians to stop?