A Ukrainian presidential adviser said on Friday that Kyiv's cross-border incursion into Russia's Kursk region was required to convince Moscow to start "fair" peace talks.

Mykhailo Podolyak said Ukraine had no interest in occupying Kursk but it had to force Russia to start talks on Kyiv's terms.

"We need to inflict significant tactical defeats on Russia," Podolyak wrote on Telegram. "In the Kursk region, we clearly see how the military tool is objectively used to convince the Russian Federation to enter into a fair negotiation process."

Ukraine mounted a cross-border assault on Russia last week and occupied part of the Kursk region.

Senior Ukrainian officials have repeatedly said Ukraine's sovereignty and territorial integrity should be fully respected in any peace agreement.

Russia invaded Ukraine in February 2022 and now controls about 18% of its territory.