"We are deeply concerned over the exchange of fire at the contact line", OSCE Minsk Group Russian Co-Chair Yuri Merzlyakov stated, APA Azeri news agency reports. When replying to the question how the MG reacted to the fact that both Armenian and Azeri sides accusing each other of the violation of the cease-fire regime appealed to the UN, Yuri Merzlyakov said that any UN member possesses the right to appeal to the organization. In his opinion, the possibilities of stabilizing the situation at the contact line of the Karabakh and Azeri armed forces have not been exhausted yet. Andrzej Kasprzyk has a mandate to assist the stabilization but not reveal those to blame for the cease-fire regime violations. It is the mission of international observers. However the parties should come to agreement and then invite peacekeeping forces to the contact line. In case one of the parties to conflict does not agree, foreign military cannot be deployed at the front line", the Russian Co-Chair said.