Syria has denied using chemical weapons while its ally Russian Federation described reports of an attack as a "provocation".
Seven nations - including the US - voted against the Russian draft which, according to US Ambassador the UN Nikki Haley, was created to give Russia a chance to approve the investigators who were chosen for the task and allow the Security Council to assess the findings of the investigation before any report was released.
The foreign ministers of Germany and Sweden are calling on Russian Federation to use its influence in Syria to pressure President Bashar Assad's government to give up its chemical weapons in the wake of a suspected poison gas attack. In 2011, the International Atomic Energy Agency reported Syria to the U.N. Security Council and General Assembly for failing to declare the construction of a nuclear reactor (which Israel destroyed in 2007), finding Damascus in non-compliance with its nuclear safeguards obligations under the Nonproliferation Treaty.
Retired Lt. Gen. Yevgeny Buzhinsky is the former chief of the Russian Defense Ministry's worldwide department.
Nebenzia warned against any US military action, saying that armed force "under mendacious pretext" and with Russian troops in Syria, "could lead to grave repercussions".
Russian-backed Syrian regime forces could ensure the safety of OPCW experts if they were to travel to the scene, he said.
Nebenzia accused the United States of trying to mislead the global community and said it is "taking one more step toward confrontation".More news: Barcelona break LaLiga's all-time unbeaten record with win over Valencia
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Europe's airspace authorities warned aircraft to be careful when flying close to Syria because of possible military action.
USA ambassador to the UN, Nikki Haley, said Russian Federation was protecting a "monster" in Assad. May says the need to attack is too "urgent" to ask parliament.
"Let them go through with it or shut up", said a participant in an online poll asking if Syrians were afraid of a USA attack.
Moscow, however, has denied the Syrian government was behind the strike, and has instead said the attack was staged by militants.
Some diplomats said there were several arguments to justify bombing Syria over the suspected chemical weapons attack.
Despite the global revulsion over chemical weapons attacks, the death toll from such incidents in Syria is only a fraction of the hundreds of thousands of combatants and civilians killed since the war began in 2011. "Unfortunately, chemical weapons use to injure and kill innocent Syrian civilians has become all too common".
Trump - who previous year launched a missile strike on a Syrian air base after sarin was used in the town of Khan Sheikhun - warned after the latest accusations that there would be a "big price to pay".
Russian ambassador Nebenzia has already said, however, that it contains "some unacceptable elements", but it is unclear if they were willing to negotiate on it.
It would have further directed the mechanism to make full use of all credible, verified and corroborated evidence collected by the OPCW fact-finding mission, while also directing it to collect and examine additional information and sources not obtained or prepared by the mission, including all information provided by the Government of Syria and others on the activities of non-State actors.