Russia and the United States have announced a landmark truce in war-torn Syria, which would take effect from Saturday, but said the ''cessation of hostilities'' does not include the Islamic State and Al-Nusra Front, the main jihadist factions.
The truce called by the big two, however, received only conditional acceptance from the leading opposition group in the five-year conflict that has brought Syria to ruin.
Any pause in the fighting will be effective only if Syria's warring factions and the jihadist elements follow a cease-fire, say analysts.
Israel said it was skeptical the deal would hold, saying any pause in the fighting would be dependent on Russia, Iran and President Bashar al-Assad.
As the Syrian conflict is entering its sixth year, a UN human rights panel reported that civilians are bearing the brunt of intensifying hostilities conducted by an ever-increasing number of warring parties, with aerial bombardments by pro-government forces leaving ''few safe places.''
The report, the commission's eleventh to the Council, draws on 415 interviews with victims and eyewitnesses in and outside the country, collected between July 2015 and January 2016.
''As their country is reduced to ruins around them, Syrian men, women and children – often the objects of deliberate attack – are fleeing their homes in an uncertain and often perilous search for safe haven,'' said Commission Chair Paulo Sérgio Pinheiro.
''We are seeing an overwhelming yet consistent intensification of external military involvement in Syria by all parties, with devastating consequences for civilians and various communities,'' he stressed, adding that: ''With the intensification of airstrikes, there are few safe places for civilians.''
He also emphasized that ''relevant Security Council resolutions remain largely unheeded and unimplemented.''
The report further alleges crimes against humanity continue to be committed by government forces and by terrorist groups, such as the Islamic State of Iraq and the Levant, or ISIL/Da'esh. "The commission of war crimes by belligerents is rampant," it added.
Aerial bombardments by pro-government forces of areas not controlled by the government have caused hundreds of civilian casualties, mass displacements, and destruction of vital civilian infrastructure, the report notes.
All warring parties, including pro-government forces, anti-government armed groups, and the terrorist groups, such as ISIL/Da'esh and Jabhat al-Nusra, carry out indiscriminate attacks by firing shells onto civilian-inhabited areas under control of the opposition, the report says.
''The damage wrought on Syria by this war cannot be measured solely by loss of life and the physical destruction of the country,'' said Commissioner Vitit Muntarbhorn. ''The war has also devastated the nation of Syria, ripping asunder the ties that bind its communities and cultures together.''
The report also finds that cultural heritage sites, which are important to Syria and the world, are also being destroyed and damaged through deliberate and incidental attacks.
The report emphasises the need for concerted and sustained international action to find a political solution to end the violence and to stop the rampancy of war crimes and grave violations of human rights.