Following the arrival of NATO Secretary General Jens Stoltenberg in Ukraine on Thursday, Russia reaffirmed its wartime goal of preventing the neighbouring country from joining the military alliance.
The Kremlin also rejected a Ukrainian suggestion that a double for Russian President Vladimir Putin was actually the person on the ground visiting troops recently and not the Russian leader himself.
Kremlin spokesman Dmitry Peskov said on Thursday, as reported by the Interfax news agency, that Russia saw itself threatened by Ukraine's possible NATO membership "because otherwise this brings a serious, significant danger to our country, to its security."
Stoltenberg visited Kiev on Thursday for the first time since the war began.
Russia had declared its intention to demilitarize Ukraine at the start of the war nearly 14 months ago. The West is supplying the country with weapons and ammunition for its defensive struggle against the Russian invasion. Russia has accused the NATO states of allowing themselves to be drawn deeper and deeper into the war.
Peskov also commented on recent allegations from Kiev that President Vladimir Putin is using a double, saying these were "rather strange" statements.
He was referring to claims that a front-line visit by Putin to the occupied territories of Kherson and Luhansk in recent days was not real and that a Putin double was actually on the scene.
However, there is no evidence that there is actually a double of Putin at official appointments.
In fact, Putin had once said that for security reasons he had been advised to use a double at official appointments, but added: "The idea came up, but I refrained from using doubles."
