You don't scede territory in hopes that it might make your adversary content. That has basically never worked historically. Russia already has invented a pretext for "pacifying" Ukraine. The response must be sudden and overwhelming force.
Put another way, when someone has broken into your house at night when it is obviously occupied, you do not hand over your wife or children in hopes your own life may be spared. You respond with an escalation of force.
Put another way, when someone has broken into your house at night when it is obviously occupied, you do not hand over your wife or children in hopes your own life may be spared. You respond with an escalation of force.