Senior Ukrainian officials say Vladimir Putin is preparing for a major new offensive in the new year, despite a series of humiliating battlefield setbacks for Russia in recent months. In an interview with the Guardian, Ukraine’s defence minister, Oleksii Reznikov, said that while Ukraine was now able to successfully defend itself against Russia’s missile attacks targeting key infrastructure, including the energy grid, evidence was emerging that the Kremlin was preparing a broad new offensive. Reznikov’s comments echoed similar remarks made to the Economist this week – including from the Ukrainian president, Volodymyr Zelenskiy, the head of the armed forces, Gen Valerii Zaluzhnyi, and the chief of ground forces, Col Gen Oleksandr Syrskii. The briefings appeared to be part of a broad, coordinated effort to warn against complacency among western allies and highlight the continuing threat Russia poses to Ukraine. While Reznikov suggested a new offensive could happen by February, the other senior officials indicated they believed it might come as early as January. Referring to Russia’s partial mobilisation of about 300,000 soldiers, Reznikov suggested that while half – often after receiving minimal training – were being used to reinforce Moscow’s forces after a series of battlefield setbacks, the remainder were being prepared more thoroughly for future offensives. “The second part of the mobilisation, 150,000 approximately, started their training courses in different camps,” said Reznikov, speaking of Russia’s mobilisation drive, which started in October. “The [draftees] do a minimum of three months to prepare. It means they are trying to start the next wave of the offensive probably in February, like last year. That’s their plan.” The warnings come amid evidence of Putin’s continuing desires to continue the war into next year, including missile procurement efforts from Iran, and analysis by Russian commentators suggesting that the Kremlin sees no way of retreating from the conflict. Reznikov said he expected Russia would continue to mobilise its citizens beyond the current partial mobilisation, describing the main tactic of Russian commanders as a “meat grinder” whereby they throw as many bodies at a battle as possible in the hope they will overwhelm the smaller Ukrainian force. “The Kremlin is trying to find new solutions [for] how to get the victory,” said Reznikov. In the Economist, Gen Zaluzhnyi delivered a similar warning, discounting some western claims that Putin’s mobilisation had largely been a failure. “Russian mobilisation has worked,” said Zaluzhnyi. “They are 100% being prepared.” He added that a major new Russian attack could come “in February, at best in March and at worst at the end of January”. In another briefing on Thursday, the deputy defence minister Hanna Maliar also warned against allowing complacency to set in after recent Russian military setbacks. “We and the world should not relax, because the ultimate goal of the Russian Federation is to conquer all of Ukraine, and then it can move on,” Maliar said. The assessment that Russia may be preparing a new large-scale campaign against Ukraine in the coming months runs counter to intelligence briefings and recent analysis that has suggested the tempo of the war – and Russian efforts – will slow through the depths of the Ukrainian winter. With Ukrainian troops being trained in a number of western countries, and arriving foreign-trained soldiers being seeded in units across the country, Reznikov said Ukraine’s hybrid tactics, well-trained troops and the wishlist of weapons it hopes to receive from allies, would enable it to withstand fresh attacks. “If it was meat grinder against meat grinder, we would lose. It was a mistake to perceive us as a small Soviet army [that] will fight a big Soviet army. Certainly, a big Soviet army would win and a small Soviet army would lose but we are not a Soviet army.” Speaking hours after another mass drone attack on Kyiv on Wednesday, when Ukraine’s air defence said it shot down all 13 drones that were launched, Reznikov said he believed Ukraine was now winning against Russia in the air. Russia began targeting Ukrainian energy facilities on a regular basis in the autumn after Moscow’s forces were pushed out of Kharkiv and the Crimean Bridge attacked. The aim was to debilitate Ukraine to increase the chances of success on the battlefield. However, since then, Ukraine has shown increasing skill in shooting down rockets and drones. Reznikov said Ukraine’s air defence systems had increased their efficiency from 50% at the beginning of the war to 80% in December. He also gave the example of the previous barrage on 5 December, when Ukraine shot down 60 out of 70 rockets fired by Russia. Ukraine has also been appealing for new weapons systems including better air defences, even as it appears to have escalated its targeting of bases in Russia, including with drones, strikes Reznikov declined to comment on. Ukraine was using a combination of air defence systems gifted by its partners, Soviet-era systems and repurposed mobile machine guns to combat the threat, said Reznikov. On Tuesday, CNN reported that US officials had agreed to send Ukraine powerful and effective US-made Patriot air defence systems that Ukraine has been asking for for months. The US had previously worried the long-range Patriot defence systems, which can travel up to 60 miles, would provoke an escalation from Russia. Ukraine has had to constantly prove to its partners that it is worth investing in its military through wins on the battlefield. Reznikov gave the example of how Ukraine sank the Moskva warship with a Ukrainian-made Neptune system in April and how each win has led to more supplies. “When we used a Ukrainian invention, the Neptune, and we sank the warship Moskva … after that, we get [US-made] Harpoons to defend our sea line,” he said. The series of wins had created something that transcended diplomatic trust between Ukraine and its partners, said Reznikov. “It’s something more: you became the believer of us and you started to invest, not only, I would say, not only weapons in Ukraine, [but] because you want to see the new Ukraine after this victory, not the old Soviet Ukraine.” The UK and other western allies are in the process of training thousands of Ukrainian troops, from novices, to specialising those who are already experienced soldiers. Reznikov claims that Russia, meanwhile, is “only using Soviet systems and training courses”. The comments came as fighting continued on the southern and eastern fronts. In the south, Russian shelling on Thursday killed two people in the city of Kherson and left it without power, Ukrainian officials said, in the latest bombardments since Kyiv recaptured the city last month. The deputy head of the president’s office, Kyrylo Tymoshenko, said on social media that Russian forces had shelled the city centre.