"Over the past week, the Russian-Ukrainian border has been crossed by enemy military hardware from the Russian Federation, including four Ural trucks, four 122mm howitzers, two Grad multiple rocket missile systems and four armored combat vehicles," speaker for the ATO at Ukraine's Defense Ministry Andriy Lysenko said at a briefing in Kyiv on Monday, an UNIAN correspondent reports.

Read alsoUkraine reports 1 WIA amid 15 enemy attacks in last dayAccording to Lysenko, it is also recorded an increase in the volume of supplies of fuel and lubricants from Russia to the occupied territories of Ukraine.

"At the same time, there is growing dissatisfaction with the terms of military service and the low level of payment among the militants of the Russian occupation forces. Many of them are trying to retire from the ranks of illegal armed groups to further enrollment in private military companies and service in crisis regions of the world, particularly in Syria," he said.