"Donbass is and will be Ukrainian (region), the Ukrainian and Russian languages will be freely used there," the president said during a working visit to Severodonetsk in the Lugansk region.
He noted that Kiev does not support the war, but is seeking peace.
Economic Renewal to Begin in Donbass Next Year if Stable Ceasefire Observed
The truce in eastern Ukraine was a key provision of the February Minsk peace agreement but the fighting in Donbass continues.
"If we prevent the further escalation and maintain at least a truce, but a stable and reliable one, then next year we will be able to resume economic growth and feel the first results of the reforms," Poroshenko said.
He added that there is no alternative to a political and diplomatic settlement of the conflict in eastern Ukraine.
In November 2014, Poroshenko signed a decree imposing an economic blockade on Donbass and withdrawing all state-funded health, education and social protection organizations from the region.
Despite the fact that Minsk agreements stipulated the removal of the blockade, the authorities of the self-proclaimed Donetsk and Lugansk people's republics point out that Kiev has not eased the blockade.
