The message from Vladimir Putin’s ominous morning speech, which marked the biggest escalation of the war in Ukraine since the February 24 invasion, was clear: Russia is willing to use nuclear weapons if Ukraine continues its aggressive operations. While the longtime Russian leader has flirted with the grim prospect of using nuclear weapons in the past, experts say his latest remarks went further, stoking fears around the world of an unprecedented nuclear disaster. Addressing the nation on Wednesday, Putin confirmed that he planned to annex four partially occupied regions of southern and eastern Ukraine after “referendums” orchestrated by the Kremlin this weekend. He added that he was ready to use “all means” to defend the “territorial integrity” of Russian-occupied territories and their people. “Putin’s statements go beyond Russian nuclear doctrine, which suggests only Russia’s first use in a conventional war when the very existence of the state is threatened,” said Andrey Baklitskiy, a senior researcher at the Weapons of Mass Destruction and Other Strategic Weapons Program at the the United Nations Institute for Disarmament Research. Ukraine, which has been making rapid military gains in recent weeks, said it would continue its efforts to liberate the occupied territories, with Ukrainian President Volodymyr Zelenskiy saying on Wednesday that the referendums would “act step by step to the liberation of our country. “. This means that Putin’s resolve will likely be tested in the coming weeks. Baklitsky said the concept of “territorial integrity” put forward by Putin was “difficult” given that Russia planned to absorb four Ukrainian regions where heavy fighting is taking place. “What would it mean if Ukraine reclaimed territory that Russia considers its own and Putin didn’t use nuclear weapons in response?” Baklitsky added. “Coming from the person who has the sole authority to make decisions about Russian nuclear weapons, this should be taken seriously.” Mark Galeotti, an expert on Russian politics, also said Putin’s nuclear threats were unprecedented, but questioned whether the Russian leader was willing to follow through on his threats, which would mean de facto nuclear war. “It’s unlikely to assume that anyone who claims they’re not bluffing is bluffing, but the credibility of a threat to risk thermonuclear Armageddon if Ukrainian forces continue to move into territories that are still legally Ukrainian is questionable.” Instead, Galeotti argued, the apocalyptic threats could have been intended to force the West and Ukraine to accept Russia’s territorial gains in the war. Zelensky, in an interview with German newspaper Bild on Wednesday, also said he did not believe Putin would use nuclear weapons. “I don’t think the world will allow him to use these weapons,” he said. The Ukrainian leader, however, did not rule out a Russian nuclear attack, saying “we cannot look at Putin’s head.” For millions of Russians, the most disturbing takeaway from Putin’s speech will be that they and their loved ones could soon be fighting and dying for their president’s illusory purposes. Vladimir Putin announces partial mobilization of Russian troops for Ukraine – video Since the start of the war, Putin has sought to shield his population from the reality of war, with the Kremlin eager to cultivate a sense of normalcy on the streets of Moscow and other major cities. Many have responded to these efforts, with polls consistently showing that the average Russian is quickly distancing himself from the conflict. But with the decision to announce the first mobilization since the second world war and call up 300,000 mostly young Russians, this unwritten social contract has now been canceled and war will enter the households of thousands of families across the country. Archie Bland and Nimo Omer take you to the top stories and what they mean, free every weekday morning Privacy Notice: Newsletters may contain information about charities, online advertising and content sponsored by external parties. For more information, see our Privacy Policy. We use Google reCaptcha to protect our website and Google’s Privacy Policy and Terms of Service apply. Anti-war protests across the country were immediately announced by jailed opposition leader Alexei Navalny on Wednesday, but with much of the opposition either in exile or behind bars, observers said they did not expect Russians to take to the streets en masse. “Russia’s oppressed society will accept this meekly,” said Andrei Kolesnikov of the Carnegie Moscow Center thinktank. “They will deal with the matter in their own practical way, avoiding the plan as best they can.” On Wednesday morning some were frantically looking for a way out of the country. Direct flights from Moscow to Istanbul, Yerevan, Tashkent and Baku, the capitals of countries that allow Russians to enter visa-free, are sold out, while the cheapest flights from Moscow to Dubai cost around 350,000 rubles (£5,000 ), a very high end for most. Land exit options were severely limited this week when four of the five EU countries bordering Russia announced they would no longer allow Russians to enter on tourist visas. Searches for the phrase “How to break your arm” and “How to avoid the draft” surged on Google and Russian search engine Yandex on Wednesday, another stark indication of the lengths many were willing to go to avoid the draft . The offering of bribes to avoid the military, already a thriving industry before the war, is likely to become much more common in the coming weeks. Wednesday also brought bad news for the thousands of troops fighting in Ukraine, a force plagued by morale and discipline issues. According to a government decree posted on the Kremlin’s website, the contracts of soldiers currently fighting in Ukraine will be automatically extended “until the end of the period of partial mobilization.” “I can’t keep fighting forever. Mentally and physically, I’m exhausted,” said one soldier, who had been fighting in Ukraine since April and planned to leave the army when his contract expired in November. For Kolesnikov, Putin’s latest move is a sign of the growing desperation of a leader who is playing the last cards at his disposal to prevent a military collapse that would pose the biggest threat to his regime since he took power before more than 20 years. “This is clearly the emotional and spontaneous decision of a cornered person,” he said.