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In a video address, Mr Zelenskyy said Russian forces had “destroyed the town’s critical infrastructure and damaged 90 per cent of buildings”.
“We are doing everything we can to contain this offensive. There was not a day when we did not try to find more weapons or modern weapons to protect our land and our people. I am grateful to everyone who defends Severodonetsk and demonstrates to the occupiers that peace will still be ours,” he said.
Mr Zelenskyy, who visited the country’s second-largest city of Kharkiv on Sunday on his first trip outside the Kyiv region since the start of the Russian invasion, condemned the damage to the city from Russian bombardment.
“Russia has already lost not only the battle for Kharkiv, not only the battle for Kyiv and the north of our country. It has lost its own future and any cultural ties with the free world,” he said.
“One-third of the Kharkiv region is still under occupation. We will definitely vacate the whole territory, and everyone should work for this result in positions at both the local and state levels.”
While praising Kharkiv regional officials for their work, Mr Zelenskyy said that he fired the regional head of the country’s security agency, the SBU, for his poor performance.
“He did not work to defend the city from the first days of the full-scale war but thought only of himself personally. What were his motives? Police are investigating,” Mr Zelenskyy said.
He also met regional officials to discuss the military situation and prospects for rebuilding housing stock.
On his visit to Kharkiv, Mr Zelenskyy presented medals to service personnel.
“I want to thank each of you for your service. You risk your life for all of us and for our state. Thank you for defending the independence of our country. Take care of yourselves,” he said.