The monitoring mission of the Organization for Security and Cooperation in Europe (OSCE) in eastern Ukraine has warned that violations of a cease-fire agreement are becoming more frequent and severe.
Alexander Hug, the OSCE's deputy chief monitor, told the UN Security Council by videoconference on June 5 that OSCE monitors have noted the movement and presence of heavy weapons, and their use, in areas where they are prohibited by the cease-fire agreement signed in the Belarus capital Minsk in February.
Hug called on all sides to urgently return to the negotiating table
The Security Council meeting on Ukraine comes two days after the rebel forces attacked the government-held city of Maryinka.
Ukraine said it pulled some of its heavy weaponry back towards the frontline to repulse two offensives by the separatists in which tanks and heavy weapons were used.
UN political chief Jeffrey Feltman said 28 people including nine civilians were killed in the clashes around Maryinka
More than 6,400 people have been killed since fighting erupted in eastern Ukraine between government forces and Russian-backed separatists in April 2014.