The Russian army's advance in the Kursk region against Ukrainian troops is threatening Kyiv's only territorial bargaining card at a critical time in the war, CNN reported on Sunday.

Last August, Ukraine had launched its surprising incursion into Kursk and managed to capture territory that was seen not only as a useful possession to be exchanged for Russian-occupied territory but also was a campaign that sought to divert Moscow's resources from the front lines in the east.

However, observers now say that the current Russian advances have put Ukraine in a much weaker position and are likely to become more intense, especially since Kyiv also faces a completely different diplomatic picture after President Donald Trump halted U.S. military aid and intelligence sharing, according to CNN.

In addition, the arrival of some 12,000 North Korean soldiers in Kursk has bolstered Russia's offensive operations, and Ukraine has now lost about half of the territory it once occupied in Kursk.

Ukraine's military said that the Russian forces had gained a "foothold" on the outskirts of Sudzha, a border town, adding that "currently, the Russian special forces are being identified, blocked, and destroyed. The enemy losses in the Sudzha area are very significant."

But in the face of Moscow's gains so far in the region, some Ukrainians have suggested that the Kursk incursion may have exhausted its strategic value.

"I didn't think I would ever say this. But maybe it's time to 'close the shop' from the Kursk direction. It's hard for our guys there," said Serhii Flesh. "As a diversion of enemy resources, I think this operation has long since justified itself. As a political bargaining card, it is now questionable."

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