A still image from a video released by the Azerbaijan's Defence Ministry shows members of Azeri armed forces firing artillery during clashes between Armenia and Azerbaijan over the territory of Nagorno-Karabakh in an unidentified location, in this still image from footage released September 28, 2020. Fighting escalated sharply on Monday between Azerbaijan and its ethnic Armenian mountain enclave of Nagorno-Karabakh, and at least 55 people were killed in a second day of heavy clashes. Defence Ministry of Azerbaijan/Handout via REUTERS

A still image from a video released by the Azerbaijan's Defence Ministry shows members of Azeri armed forces firing artillery during clashes between Armenia and Azerbaijan over the territory of Nagorno-Karabakh in an unidentified location, in this still image from footage released September 28, 2020. The two sides pounded each other with rockets and artillery in the fiercest round of the decades-old conflict in more than a quarter of a century. Defence Ministry of Azerbaijan/Handout via REUTERS

A still image from a video released by the army of the self-proclaimed Nagorno-Karabakh breakaway region shows bodies of men in military uniform, who are said to be Azeri military personnel, in an unidentified location, in this still image from footage released September 28, 2020. Nagorno-Karabakh said 53 of its soldiers had been killed in fighting with Azeri forces on Monday, after saying that 31 of its servicemen had been killed on Sunday and 200 wounded when Azerbaijan attacked. Self-Proclaimed Artsakh Defence Army Handout/Reuters TV via REUTERS

A still image from a video released by the Armenian Defence Ministry shows what is said to be Azerbaijani armoured vehicles, one of which is destroyed by Armenian armed forces in the breakaway region of Nagorno-Karabakh, in this still image from footage released September 27, 2020. Defence Ministry of Armenia/Handout via REUTERS

A still image from a video released by the Armenian Defence Ministry shows what is said to be Azerbaijani armoured vehicles, one of which is destroyed by Armenian armed forces in the breakaway region of Nagorno-Karabakh, in this still image from footage released September 27, 2020. Defence Ministry of Armenia/Handout via REUTERS

An interior view shows a house, which locals said was damaged during a recent shelling by Azeri forces, in the town of Martuni in the breakaway Nagorno-Karabakh region, September 28, 2020. Foreign Ministry of Armenia/Handout via REUTERS