"Unfortunately, the ceasefire is not observed by the terrorist groups. Unfortunately, there were 33 attacks with the use of mortars and artillery systems yesterday," Poltorak said at a briefing in Kharkiv on Monday.

He noted that the relevant actions were supported by the Russian Federation. "It is a testament to the aggressive policy, which is supported by the Russian Federation, and the aggressive behavior of the terrorist groups in Donetsk and Luhansk," the Minister said.

Read alsoMilitants attack Ukraine 39 times in last dayAt the same time, Poltorak assured that the Armed Forces of Ukraine fully control the situation at the front and, in the case of aggravation, are ready to give a fitting rebuff.

"The situation in the zone of the Anti-Terrorist Operation is under full control of the Armed Forces of Ukraine. The number of personnel, equipment, weapons, which are now in the ATO zone, fully ensure the inviolability of the borders and provide the fulfillment of the tasks assigned to the Armed Forces of Ukraine. We are monitoring the situation and are ready to react if it worsens," Poltorak said.

As UNIAN reported earlier, Ambassador Martin Sajdik, the Special Representative of the OSCE Chairperson-in-Office in Ukraine and in the Trilateral Contact Group (TCG) on the implementation of the peace plan in the east of Ukraine, announced that the TCG and Russian-controlled militants had declared their commitments to a sustainable ceasefire in Donbas from midnight on December 24.