Ukrainian President Volodymyr Zelenskyy is calling on Russian forces to heed the calls of residents in the occupied city of Melitopol who protested to demand their mayor be freed.

Zelenskyy, who spoke earlier Saturday with the leaders of Germany and France, said the detention of Melitopol Mayor Ivan Fedorov was an attempt "to bring the city to its knees."

He said that Ukraine expects "the leaders of the world to show how they can influence the liberation (of) a man who personifies Ukrainians who do not give up."

Zelenskyy also encouraged Ukrainians to keep fighting, saying it was "impossible to say how many days we will still need to free our land, but it is possible to say that we will do it."