A close adviser to the commander-in-chief of Ukraine’s army has been killed after a booby-trapped birthday present he was given exploded. “Under tragic circumstances, my assistant and close friend, Major Gennadiy Chastiakov, was killed … on his birthday,” Gen Valeri Zaluzhni posted on Telegram on Monday, saying that an “unknown explosive device detonated in one of his gifts”. Chastiakov leaves a wife and four children, he said. Zaluzhny added that since Russia invaded Ukraine in February 2022, Chastiakov had been “fully devoting his life to the armed forces of Ukraine and the fight against Russian aggression”. Attacks targeting Ukrainian leaders have been relatively rare since Moscow invaded, but there have been several attacks on Russian nationalists, which Russia has blamed on Ukraine. In April, a blast from a statuette rigged with explosives killed the 40-year-old pro-Kremlin military blogger Vladlen Tatarsky. The Kremlin said the attack had been orchestrated by Ukraine with the help of supporters of the jailed Kremlin critic Alexei Navalny, but observers said the bombing could have been engineered to justify a further crackdown on critics. Last August, Darya Dugina, the daughter of a prominent ultranationalist intellectual, was killed in a car bombing outside Moscow, which Russia also attributed to Ukraine. Also on Monday, Ukrainian forces said they had successfully destroyed a Russian ship in the Kerch shipyard in annexed Crimea, and Ukraine’s president, Volodymyr Zelenskiy, said he did not believe the time was right for the country to hold elections, amid a brewing debate on the possibility of a presidential vote in 2024. All elections including the presidential vote due to take place next spring are technically cancelled under the martial law that has been in effect since the war began last year. “We must decide that now is the time of defence, the time of battle, on which the fate of the state and people depends,” Zelenskiy said in his daily address. He said it was a time for the country to be united, not divided, and added: “I believe that now is not the time for elections.” Ukraine’s foreign minister said last week that Zelenskiy was weighing up whether it would be possible to hold elections next year, given the invasion. He cautioned that polling would be difficult to hold due to the large number of Ukrainians abroad and soldiers fighting on the front. Parliamentary elections that would have taken place last month have already been cancelled because of the war. Zelenskiy, who was elected in 2019, said in September he was “ready” to hold elections if necessary and was in favour of allowing international observers to monitor the vote. The Ukrainian leader’s approval rating soared after the war began, but some divisions have emerged. Former presidential aide Oleksiy Arestovych announced this week that he would run against his former boss after criticising the slow pace of the country’s counteroffensive. The sprawling frontline between the two warring sides has barely moved in almost a year, despite a Ukrainian counteroffensive that began in June. The Ukrainian president has regularly met western leaders to try to secure more air defences and stave off international fatigue with the conflict, which has now lasted for more that 600 days. Zelenskiy has also been forced to deny that the conflict has reached a deadlock, but admitted on Sunday that it had reached a “difficult situation”.