Russian President Vladimir Putin on Wednesday called up 300,000 reservists to fight in Ukraine and backed a plan to annex parts of the country, hinting to the West he was prepared to use nuclear weapons to defend Russia. It was Russia’s first such mobilisation since World War II and signified the biggest escalation of the Ukraine war since Moscow’s February 24 invasion. It followed mounting casualties and battlefield setbacks for Russian forces, who have been driven from areas they had captured in northeast Ukraine in a Ukrainian counteroffensive this month and are bogged down in the south. In an address to the nation, Putin said: “If the territorial integrity of our country is threatened, we will use all available means to protect our people – this is not a bluff”. Russia had “lots of weapons to reply”, he said. Kyiv and its Western allies responded by saying the move showed Russia’s campaign in Ukraine was failing. The allies pledged further support for President Volodymyr Zelensky’s government. Russia’s defence minister said the partial mobilisation would see 300,000 reservists with previous military experience called up. Although Russia has been involved in a number of conflicts since World War II, this was the first such call-up since then. Russian paratrooper flees to France denouncing army ‘chaos’ Zelensky said on Wednesday he did not believe the world would allow Putin to use nuclear weapons. Speaking in an interview with Germany’s BILD TV, Zelensky warned against being cowed by Putin’s threats, saying they would invite Russia to attempt to take more territory. “I don’t believe that he [Putin] will use these weapons. I don’t think the world will allow him to use these weapons,” Zelensky said. Before Putin’s address, world leaders meeting at the United Nations in New York denounced the Russian invasion of Ukraine and plans for four occupied regions to hold referendums in the coming days on joining Russia. Putin said the partial mobilisation of its 2 million-strong military reservists was to defend Russia and its territories. The West did not want peace in Ukraine, he said. He accused Washington, London, Brussels of pushing Kyiv to “transfer military operations to our territory”. Ukraine has sporadically struck targets inside Russia throughout the conflict, using long-range weapons supplied by the West. “Nuclear blackmail has also been used,” Putin said, citing Ukraine’s Zaporizhzhia nuclear power plant . Russia and Ukraine have accused each other of endangering the plant in the fighting. Moscow said on Wednesday a large-calibre shell had damaged a technical water pipe at the plant, which is occupied by Russian troops. Putin also accused officials of Nato countries of making statements about “the possibility and admissibility of using weapons of mass destruction against Russia – nuclear weapons”. “I want to remind you that our country also has various means of destruction, and in some components more modern than those of the Nato countries,” he said. Nato Secretary General Jens Stoltenberg denounced Putin’s threat to use nuclear weapons as “dangerous and reckless rhetoric”. The moblisation plan demonstrated “that the war is not going according to his plans” and it was clear that the Russian president had made “a big miscalculation”, Stoltenberg said. As for any potential Russian use of nuclear arms, “We will make sure that there is no misunderstanding in Moscow about exactly how we will react,” Stoltenberg said. Putin restated his aim was to “liberate” the Donbas, Ukraine’s industrial heartland, and said most people there did not want to return to what he called the “yoke” of Ukraine. In an apparently coordinated move, pro-Russian regional leaders on Tuesday announced referendums for September 23-27 in Luhansk, Donetsk, Kherson and Zaporizhzhia provinces, representing around 15 per cent of Ukrainian territory. Russia already considers Luhansk and Donetsk, which together make up the Donbas region that Moscow partially occupied in 2014, to be independent states. Kyiv and the West consider all parts of Ukraine held by Russian forces to be illegally occupied. Russia now holds about 60 per cent of Donetsk and had captured nearly all of Luhansk by July after slow advances during months of intense fighting. Those gains are now under threat after Russian forces were driven from neighbouring Kharkiv province this month, losing control of their main supply lines for much of the Donetsk and Luhansk front lines. Alla Pugacheva, one of Russia’s most famous women, attacks Putin’s war The Russian opposition called for street protests against Putin’s mobilisation order. Alexei Navalny, Russia’s most prominent opposition leader who is currently in prison, said Putin was sending more Russians to their death for a failing war. The Vesna anti-war coalition said: “This means that thousands of Russian men – our fathers, brothers and husbands – will be thrown into the meat grinder of war.” “Now the war has come to every home and every family.” Kremlin spokesman Dmitry Peskov declined to comment on the possibility of border closures to prevent citizens evading the call-up after reports of a surge in sales of one-way tickets out of Russia. Asked whether Russia would close its borders for those who are subject to mobilisation, Peskov said: “I can’t answer that question … There are provisions for this in the current laws.” Russian Defence Minister Sergei Shoigu said on Wednesday 5,937 Russian soldiers had been killed since the start of the conflict. But the United States in July estimated Russia’s death toll at around 15,000. German Chancellor Olaf Scholz, speaking to the UN General Assembly in New York, said Putin will only give up his “imperial ambitions” if he recognised he cannot win the war. Kyiv’s neighbour Poland said Russia would attempt to destroy Ukraine and change its borders. “We will do all we can with our allies, so that Nato supports Ukraine even more so that it can defend itself,” Polish Prime Minister Mateusz Morawiecki said. US ambassador to Ukraine Bridget Brink said Moscow had shown weakness by announcing the mobilisation and setting out the referendums in the Russian-occupied territories. China’s foreign ministry urged all parties to engage in dialogue and consultation and find a way to address the security concerns of all parties. Flights out of Russia sell out after Putin’s mobilisation call Putin’s words also hit global markets, which have see-sawed since the invasion. The euro tumbled 0.7 per cent against the dollar, European stock markets opened sharply lower, and investors piled into safe-haven bonds, pushing yields on German and US government debt down. Michel Hewson, chief markets strategist, CMC Markets, said: “It’s the fact that he’s decided to dust off the nuclear card that obviously hasn’t gone down well … I think there is a perception that he’s really upped the ante, and how does the West respond to it?” Putin calls the Russian action in Ukraine a “special military operation” to root out dangerous nationalists and “denazify” the country. The West says it is a land grab and an attempt to reconquer a country that broke free of Moscow’s rule with the break-up of the Soviet Union in 1991. Nearly 6,000 civilians have been recorded as killed – many in artillery bombardments and air strikes – although the actual casualties are much higher, the UN says. About 9,000 Ukrainian military personnel had been killed, Kyiv says.