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Ukrainian President Volodymyr Zelenskyy said Russia would not be able to win the war against his country and called on residents to do everything to make Ukraine "unbearable" for Russian troops.
In his nightly video address, Mr Zelenskyy said Russia would lose the war it started against its neighbour.
But to make Russia seek peace, Ukrainians must think of how to make “the presence of occupiers at our land even more unbearable”.
“Russia can spend enormous resources to support the war and even to counter the entire free world," Mr Zelenskyy said.
"It can take away from its people everything that could develop Russia and direct its potential to destroy the lives of neighbours. But the lessons of history are well known.
"If you are going to build a millennial Reich, you will lose. If you are going to destroy neighbours, you will lose.
"If you want to restore an old empire, you will lose. And if you went against Ukrainians, you will lose."
Mr Zelenskyy assured Ukrainians of victory and peace.
'"But in order to make it happen and happen sooner, we must think not about when and what it will be," he said.
“Ukraine is ready for peace. It was ready even when the war continued in the Donbas. It’s still ready now when the Russian invasion has become large-scale.
"But in order to make Russia seek peace, every Ukrainian men and women must fight, must defend the freedom.
"Because every day of the fight will add years and years to the peaceful life after this war, after our victory."
