President Volodymyr Zelenskyy on Friday declared that Ukraine had reached a strategic turning point in its fight with Russia, which he said was relying on conscripts, reservists and Syrian mercenaries to prop up its invasion force.
In a daily televised address in Kyiv, Zelenskyy called on the international community to ramp up sanctions pressure on Russia if it didn't back down.
"It is impossible to say how many days we still have to free Ukrainian land. But we can say we will do it. For we have already reached a strategic turning point," he said.
He said Ukraine is battling an enemy, "who collects reservists and conscripts from all over Russia to throw them into the hell of war, who came up with the idea of bringing in mercenaries against our people. Thugs from Syria."
Earlier Friday, Russian President Vladimir Putin gave the green light for the deployment of up to 16,000 volunteers from the Middle East, doubling down on an invasion the West says has been losing momentum.
Ukrainian presidential adviser Oleksiy Arestovych said the move was a sign of the Russian army's weakness.
"Where's the powerful Russian army if they can't get by without Syrians? If they want us also to kill 16,000 Syrians - let them come," Arestovych said at a televised briefing.