Lavrov said that "intelligence agencies of a state that is now striving to spearhead a Russo-phobic campaign were involved in that fabrication".
According to Syrian medics and a statement by the World Health Organisation, more than 40 people died in an April 7 strike on the former rebel outpost of Douma of symptoms consistent with the use of chemical weapons.
The military attack was ordered in coordination with France and the United Kingdom, in response to what the USA believes was a chemical attack by Syrian President Bashar al-Assad last week. Moscow also said it was calling an emergency session of the United Nations Security Council, where it is a permanent member, to discuss the "aggressive actions" of the U.S. and its allies.
Why is the West considering military action?
In his primetime address announcing the strikes, Trump accused Russian President Vladimir Putin and his government of failing to guarantee a 2013 deal that was supposed to rid Assad of his chemical weapons.
French President Emmanuel Macron also said he had "proof" that the Syrian government had attacked Douma with chemical weapons, without giving further details.
It comes after UK Prime Minister Theresa May spoke with President Trump and the pair agreed "the Assad regime had established a pattern of unsafe behaviour in relation to the use of chemical weapons".
Later, a White House briefing on a call between Trump and May said that they "continued their discussion of the need for a joint response to Syria's use of chemical weapons".
Russian Federation has described the reports of a chemical attack as a "provocation" created to justify Western intervention.
"The immediate priority is to avert the danger of war", said Ambassador Vassily Nebenzia. "I hope no one would dare to launch such an adventure now", Lavrov said.
Lavrov noted that Russian and USA militaries have a hotline to prevent incidents, adding that it's not clear if it would be sufficient amid mounting tensions.
And this line has been backed by the United Kingdom and USA who are also pointing the finger at President Bashar al-Assad's regime.
Bolton has called the Syrian civil war a "sideshow" and said he is much more concerned about Iran's role there than about whether Assad remains in power.
A fact-finding mission from the Organization for the Prohibition of Chemical Weapons is expected to arrive in Douma on Saturday. Both the Syrian and Russian governments have said they would support the study.
The council failed on Tuesday to approve three draft resolutions on chemical weapons attacks in Syria.
In April previous year Trump ordered Tomahawk strikes on the Shayrat Airbase in response to a chemical weapons attack on rebel-held Khan Sheikhun.