One of Russian President Vladimir Putin's closest aides says Russia is effectively at war with NATO nations.

Security Council Secretary Nikolai Patrushev said on Wednesday that Russia is fighting not just Ukrainian troops but also the NATO alliance.

Patrushev said the risks of sabotage and terrorism have been rising in Russian-occupied areas. He accused Western nations of trying to expand what he called hostile actions into Russian territories.

The remarks come at a time when Ukrainian troops are apparently ramping up their efforts to take back ground in the eastern region of Luhansk, as well as Kherson in the south.

On Wednesday, Luhansk Governor Serhiy Haidai said, "The de-occupation of the Luhansk region has already officially started." Ukrainian President Volodymyr Zelenskyy revealed that the country's troops have retaken settlements in Kherson.

The UK defense ministry said in its intelligence update on Thursday that Ukraine's forces started a new phase of offensive operations in Kherson on October 2. It added that Ukrainian units have pushed the front line forward by up to 20 kilometers.

The ministry also said, "Russia faces a dilemma: withdrawal of combat forces across the Dnipro makes defense of the rest of Kherson Oblast more tenable; but the political imperative will be to remain and defend."

It added that Russia currently has few additional deployable forces available to stabilize the front since it has committed the majority of its airborne forces to the defense of Kherson.

Also on Wednesday, the US-based think tank Institute for the Study of War said, "Ukraine's northern Kharkiv counteroffensive has not yet culminated after one month of successful operations." It added that Ukrainian troops are now advancing into western Luhansk.

Following its annexation of four Ukraine regions, the Putin administration will likely continue its invasion in the name of "territorial defense" of the regions.