Ukraine will not give part of its territory to the aggressor in order to stop the war, since such "primitive deals" lead to escalation, Adviser to the head of the President's Office Mykhaiol Podoliak has said.

"Ukraine will not give up part of its territory to stop the war. Because primitive 'territory for peace' deals invariably lead solely to an escalation of the conflict and the next stages of the war. Any concession to the aggressor inevitably provokes it to a sharp expansion of aggressive actions, growth of aggressive appetites and a desire to blatantly nullify international law," Podoliak said on Friday in response to comments by former U.S. President Donald Trump.

He also said "no mature and sovereign country (especially of global level and global agency) will ever agree to such deals if it wants to preserve its self-respect and freedom. And will never offer suicide to other partner countries. This is an axiom."

The day before, Trump told Reuters that in order to end the war, Ukraine may have to give part of its territory to Russia. It would be "negotiable" if he were president, he said, but the Ukrainians, who fought vigorously to protect their land, deserved a lot of credit. "I think they [Ukraine] would be entitled to keep much of what they've earned and I think that Russia likewise would agree to that. You need the right mediator, or negotiator, and we don't have that right now," Trump said.