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Ukrainian President Volodymyr Zelenskyy on Thursday said Russia had rejected a proposal for a truce over the Orthodox Christian Easter period this weekend, but said he still harboured hopes for peace.
Mr Zelenskyy made the remarks in his nightly video address. The Orthodox Easter service starts late on Saturday into Sunday morning.
The leader also thanked the US for the new package of $800 million in military aid.
The latest military aid, announced on Thursday by US President Joe Biden, includes heavy artillery, ammunition and drones for the battle in the Donbas region of eastern Ukraine.
Mr Biden pledged $1.3 billion more in total for new weapons and financial assistance to help Ukraine in its strong but increasingly difficult battle against the Russian invasion.
Mr Zelenskyy urged western countries to speed up the deliveries of weapons to help Ukraine fend off the Russian offensive.
“The invaders continue to do everything so that there are grounds for them to talk about some victories,” Mr Zelenskyy said late on Thursday.
“They are accumulating forces, driving new battalion tactical groups on to our soil. They are even trying to start the so-called ‘mobilisation’ in the occupied regions of Ukraine.”
He warned Ukrainians living in areas of southern Ukraine under the control of Russia troops not to provide them with IDs, which he said could be used to “falsify the so-called referendum” to create a Moscow-friendly government.
“And this is reality,” Mr Zelenskyy said. “Be careful.”