Russia on Thursday voiced serious concern about the escalation of tensions on the Armenia-Azerbaijan border and called on the sides to refrain from using force.

“We are seriously concerned about the aggravation of the situation on the Armenian-Azerbaijani border. We urge the sides to refrain from the use of force and to resolve all disputed issues exclusively through political and diplomatic means,” Russian Foreign Ministry spokesperson Maria Zakharova said at a press briefing referring to Azerbaijan’s attack on Armenia’s Gegharkunik Province on Tuesday, as a result of which three Armenian soldiers were killed.

She said that in the long run the main “prescription” for ensuring stability and security in the region is the immediate start of the delimitation process, which will be followed by demarcation. Zakharova said that the principle was agreed to in the joint statement the leaders of Armenia, Russia and Azerbaijan made in Sochi last year.

Zakharova stressed the need to work on the establishment of a relevant bilateral commission, assuring that Russia is ready to provide comprehensive consulting assistance.

In what appeared to be a rebuke of Baku, Zakharova also said that it will not be possible to “cast a shadow on the efforts of the Russian peacekeepers in Nagorno-Karabakh.” Her comment was prompted by a question about recent provocations by Azerbaijani forces against the civilian population of Artsakh.

“Even if someone wants to cast a shadow on our peacekeepers, they will not succeed. Their work is clear, it is for the benefit of crisis management,” Zakharova said.