The Ukranian nationalist Right sector movement has rejected the agreements reached at the Minsk summit on Thursday.

Movement's leader Dmytro Yarosh announced Friday that the organization will make every attempt to stop the implementation of the peace action plan on his social media profile, TASS information agency reported.

The sector played a key role during the anti-government protests at Ukraine's Maidan.

After the overturn of power, Yarosh held a Parliament seat at Ukrainian Parliament until mid-November when the newly-elected government proclaimed the Right sector an extremist organization and banned its representation in authorities.

Meanwhile, Ukrainian President Petro Poroshenko stated on Friday that an escalation in the tensions in Donbas is still likely, despite the Minsk settlement.

Igor Moseichuk, leader of the Azov paramilitary batallion, has also called for defyance of the Minsk accord.

"That’s an act of treason,'' he wrote on his social media profile. ''Betrayal of national interests. This is the sole way of describing the text regarding the implementation of the Minsk accord that Leonid Kuchma signed with the Donetsk and Luhansk republics on behalf of Ukraine.''

The organization still retains its parliament seats and is still beyond government control. Its forces are currently located at Mariupol.