Disagreements among member-states forced on Friday a postponement of the United Nations Human Rights Council vote on the crisis in the besieged Eastern Ghouta enclave in Syria.
The council was set to meet to vote on a British resolution condemning the violence.
The British draft introduced at an emergency council session calls for immediate humanitarian access to the area, where a controversial truce unilaterally declared by Damascus-ally Russia has been unable to produce a breakthrough.
The draft also instructs war crimes investigators from the UN-backed Commission of Inquiry for Syria to conduct an investigation into atrocities in the area, battered by a Russia-backed regime assault that began on February 18.
The British text specifically condemns "the use of chemical weapons by the Syrian authorities against civilians in the Syrian Arab Republic, including against the people living in Eastern Ghouta".
The proposal, perhaps unsurprisingly, faced opposition.
Russia does not currently hold a seat on the council -- which has 47 members rotating on three-year terms -- but it took the floor as an observer state to condemn the text, as did the Syrian regime.
The session opened with speech from UN human rights chief Zeid Ra'ad Al Hussein, who said that "what we are seeing, in Eastern Ghouta and elsewhere in Syria, are likely war crimes, and potentially crimes against humanity."
He also warned the perpetrators that they will not "get away with this."
"The wheels of justice may be slow, but they do grind", Zeid said, reiterating his call for the Syrian conflict to be referred to the International Criminal Court in The Hague.
Dozens of nations and multiple civil society groups took the floor to speak out about the crisis affecting some 400,000 civilians in Eastern Ghouta, subjected to a regime siege since 2013.
After multiple amendments were proposed to the British text, the council's rotating president, Vijoslav Suc of Slovenia, was forced to postpone a vote until Monday.
Later on Friday, US President Donald Trump and German Chancellor Angela Merkel discussed Syria in a telephone call.
They "urge Russia to end its involvement in the bombing of Eastern Ghouta and to persuade the regime to stop its offensive operations against civilian areas", a chancellery statement said.
Bashar al-Assad's regime "must be held accountable" for the attacks on Eastern Ghouta and the humanitarian crisis in the rebel-held enclave, they agreed in the conversation Thursday.
"This applies both to the Assad regime's deployment of chemical weapons and for its attacks against civilians and the blockade of humanitarian support."
"Both agreed that the Syrian regime and its Russian and Iranian allies are urged to promptly and fully implement" a UN Security Council resolution that calls "for a prompt ceasefire in Syria", said the statement.
