Moscow, Russia - Russia will "definitely" respond to a Ukrainian attack on a southern airfield using US-supplied ATACMS missiles, the Kremlin said Thursday, amid warnings from the Pentagon of a possible hypersonic missile strike.

President Vladimir Putin has previously threatened to launch its new hypersonic ballistic missile, named Oreshnik, at the center of Kyiv if Ukraine does not halt its attacks on Russian territory using US-supplied ATACMS missiles.

Russia's defense ministry on Wednesday accused Ukraine of firing the missiles in an overnight attack on an airfield in the port city of Taganrog in the southern Rostov region.

A response "will follow when, and in a way that is deemed, appropriate. It will definitely follow," Kremlin spokesperson Dmitry Peskov told reporters.

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He did not provide details of how Russia might retaliate.

Washington only recently gave Kyiv permission to fire ATACMS on Russian territory, following months of requests.

The US warned Wednesday, "based on an intelligence assessment," that Russia could be preparing to fire Oreshnik missiles at Ukraine again in the coming days.

Both sides have escalated aerial attacks in recent months as Russia's troops advance on the battlefield.

Russia's defense ministry said Thursday its troops had recaptured a settlement in the western Kursk region, where Ukraine launched a shock cross-border offensive in August.

It also said it had captured a tiny settlement in Ukraine's eastern Donetsk region, where it has been grinding forward for months.