Senior Russian figures, including the head of the military, have warned that U.S. missiles will be shot down and their launch sites targeted if Russian personnel come under threat. Putin and Macron instructed their foreign and defense ministers to maintain close contact to "de-escalate the situation", the Kremlin said.
Mr Nebenzia also called for the UN Security Council to meet again on Friday to discuss the possibility of Western military action.
At the White House on Thursday, Trump discussed Syria with national security aides, including Mattis, Joints Chief of Staff Chairman Joseph Dunford and USA ambassador to the United States Nikki Haley.
"It's harder to track, attribute and respond immediately to a cyber attack. than it is to know who fired a missile", the official said. During the conversation, our President quoted the public statement of the French leader regarding these "facts" and he asked to share them since, he said, we are the first ones who would like to put an end to such practices - the use of Chemical weapons.
The Russian military says that an alleged chemical attack in Syria was staged and directed by Britain. On Wednesday, Virginia State Senator Richard H. Black (R-Loudon) stood on the floor of the state Senate and gave a speech defending Assad and alleging that the chemical attack last weekend was a hoax.
The Russian Foreign Ministry also said that following Syrian rebels' withdrawal from the eastern Ghouta suburbs of Damascus, stockpiles of chemical agents were found there.
"By continuing to employ chemical weapons against innocent Syrian civilians, the Assad regime has violated global law and abandoned its own commitments to the worldwide community", she told reporters. He added that Washington seems determined to take military action in Syria and this is unsafe.
"I hope no one would dare to launch such an adventure now", he said. Russian officials beyond Mr. Putin have suggested that the aim of these USA -led airstrikes were essentially to prevent the OPCW from carrying out its work.
She said "the United States estimates that (President Bashar) Assad has used chemical weapons in the Syrian war at least 50 times".
But the Syria conflict is a complex web of overlapping wars which have drawn in several world powers, and the risk of miscalculation is as high as Trump's Twitter rhetoric is provocative.
The Kremlin also said on Monday that British allegations that chemical weapons inspectors were not being allowed access to Douma were groundless, adding Russian Federation has consistently supported an investigation into the suspected gas attack.
The US and Russian militaries have sought to avoid conflict in Syria, notably past year in the Euphrates River Valley where they supported rival sides in the campaign against Islamic State militants.
"The mission of the OPCW has set off to Syria not so quickly and without abundant enthusiasm but under our and Syrian pressure", Lavrov said.
The UK intelligence services received information that associated with the Russian authorities, the hackers allegedly going to stage a cyber attack in order to discredit government Ministers Theresa may and other senior officials.
"Did a chemical weapons attack happen?" US officials had earlier said that Trump had pressed for a more aggressive USA strike against Syria than his military chiefs had recommended.