President of Ukraine Petro Poroshenko has said that the Russian side hasn't observed the ceasefire regime in Donbas for a single day since April 1.

"Today the chief of the General Staff and the defense minister reported me that the Russian side did not observe the ceasefire regime for a single day," he said at a press conference after talks with Latvian President Raimonds Vejonis in Riga on Tuesday.

"I am grateful to our European partners who are ready to extend sanctions against Russia in case the latter fails to demonstrate its readiness to cease fire and to implement the security package," the Ukrainian president said.

Vejonis regretted that the April 1 ceasefire deal for Donbas had been marred. "We were happy to hear about the agreement to cease fire in Donbas on April 1, yet we are disappointed that bombardments in Donbas continue and people are dying," he said, answering an Interfax-Ukraine question.

The agreements are not being implemented although the truce and the withdrawal of heavy weapons are important factors in the fulfillment of the Minsk Agreements, Vejonis said. "It is very important to ensure that Russia participates in this dialogue and demonstrates constructive behavior in order to resolve this conflict. Latvia and the international community hope that Russia will actively participate in the dialogue in order to stop the bloodshed in Donbas," the Latvian president said.

It was agreed at the March 29 meeting of the Trilateral Contact Group for Donbas in Minsk to cease fire in the conflict zone on April 1.