Following a huge counterattack in Ukraine’s northeast, which saw the fleeing Russian army leaving thousands of kilometres of hard-won gains, Mr Putin took the drastic step of announcing a partial mobilisation of civilians in his first address to the nation since launching his invasion seven months ago.
Sparking fears of a descent into apocalyptic nuclear war, the Russian leader accused the West of “nuclear blackmail” and said Moscow was ready to use “all the means at our disposal”, adding: “I’m not bluffing.”
Speaking to the BBC as a week of intense discussion of the war at the United Nations general assembly in New York came to a close, the EU’s foreign policy chief warned on Saturday: “When people say it is not a bluff, you have to take them seriously.”
Mr Borrell added: “Certainly it’s a dangerous moment because the Russian army has been pushed into a corner, and Putin’s reaction – threatening using nuclear arms – is very bad.”
The bloc’s high representative for foreign affairs and security policy said that a “diplomatic solution” to the war must be reached with Mr Putin, one that “preserves the sovereignty and territorial integrity of Ukraine”.
Calling on Mr Putin to play his part in reaching a negotiated solution, Mr Borrell said that “in order to dance the tango, you need two”, as he lamented that the Kremlin had been unrelenting in its response to diplomatic efforts.
“Everybody who has gone to Moscow, to the Kremlin to talk to Putin, they came back with the same answer: ‘I [Putin] have military objectives, and if I don’t get these military objectives I will continue the fight.’ This is certainly a worrisome direction, but we have to continue to support Ukraine,” Mr Borrell said.
In a speech to the UN this week via videolink, Ukrainian president Volodymr Zelensky declared that, for Kyiv, Russia’s assault had resulted in “a war for life”, as he outlined five conditions for a peace deal with Russia, including that Moscow be stripped of its position as a permanent member of the UN Security Council.
After the speech, Mr Borrell announced that the EU would prepare to impose new sanctions on Russia and answer Mr Zelensky’s fresh call for further military support for Ukraine.
Denouncing Mr Putin’s “cynical” threat to use nuclear weapons as “a real danger to the whole world”, Mr Borrell said that the Russian president appeared to be “doubling down a failing strategy” out of “panic and desperation”.
The highly effective Ukrainian counterattack this month appears to have severely shaken Mr Putin. Kyiv’s forces retook huge swathes of the Kharkiv region and re-entered Luhansk in a symbolic victory that battered Mr Putin’s stated war aim of seizing control of the Donbas region.
In an apparent bid to shore up Moscow’s existing gains in the face of the rapidly advancing Ukrainian counter-assault, Mr Putin announced this week that referenda on joining Russia would be held in four regions held by Moscow-backed forces.
As votes began on Friday in Luhansk, Kherson and the partly Russian-controlled Zaporizhzhia and Donetsk regions, journalists and officials reported that armed groups had been sent to search homes and coerce people into going out and taking part in the referendum.
The results of the votes – widely denounced as a sham – will be announced on Tuesday, in a move that looks set to considerably escalate the war. Mr Putin’s nuclear threats have come as Moscow has repeatedly warned that any attack on the newly annexed regions would be considered an attack on Russian territory.