Ukrainian President Volodymyr Zelenskyy told CBS News on Sunday that recognizing Russia's annexation of the Crimean Peninsula was one of his red lines in ongoing peace talks between the two countries.

Zelenskyy suggested during his appearance on "60 Minutes" that although the likelihood of ending the war soon is dim, direct peace talks between him and Russian President Vladimir Putin could result in a temporary cease-fire and corridors for fleeing civilians.

"I think we've already given up a lot of lives, so we need to stand firm for as long as we can. But this is life. Different things happen," Zelenskyy said regarding the probability of peace.

The Ukrainian president acknowledged that Russia wants Crimea and most likely seeks to annex more parts of eastern and southern Ukraine. Still, he told the network he was unwilling to consider the proposition.

"We understand the Russian side. We understand one of their provisions has always been to recognize Crimea as Russian territory. I would definitely not let them recognize that," Zelenskyy said.

"I clearly understand that questions like this would be raised in negotiations if there ever are any, but we were not willing to give up our territory from the beginning. Had we been willing to be giving up the territory, there would have been no war," he continued.

Zelenskyy refused to outline exactly what a win would look like for the Ukrainian people but said the return of refugees, the end of shelling, the re-incorporation of territory, and the withdrawal of Russian troops would certainly "feel" like victory.

"I understand they [Russia] will not withdraw from Crimea and will be arguing and negotiating for one territory or another in the south of our country, the Donbas. I know exactly what has happened after which we can say 'this is victory,' but if you don't mind, I'm not going to talk about it just yet," the president said.

The comments from Zelenskyy come as reports have Russia amassing "tens of thousands" of troops for a renewed offensive against the Donbas region, according to The Washington Post.

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