A decision to take action has not been made, but one administration official with direct knowledge of the current situation told CNN the military "could respond very quickly" if Syria launched a chemical weapons attack, and the initial targeting data assembled would give the Pentagon a head start if the President decides to take action.

US officials claim they are worried that an impending assault by Syria forces on the terrorists in Idlib could involve the use of chemical weapons, an issue that Damascus has dismissed as false lies by Washington.

On Friday, US Secretary of State Mike Pompeo warned Russia's foreign minister on Twitter, "Sergey Lavrov is defending Syrian and Russian assault on Idlib. The Russians and Assad agreed not to permit this. The US sees this as an escalation of an already dangerous conflict."

On Thursday, Lavrov told Western nations not to "play with fire" over Idlib.

"It's well known that the progress of Syrian resolution, humanitarian solutions and fight against terrorism is not to everyone's liking," Lavrov said, adding that the White Helmets, a group of purportedly unarmed volunteer rescue workers, were preparing to stage a chemical strike to blame on the Syrian government as a pretext for military action.

"Another such provocation is being prepared in order to hinder the anti-terroristic operation in Idlib, and we, having our facts on the table, through our Defense Ministry and Foreign Ministry clearly and firmly warned our Western partners -- don't play with fire," Lavrov said.

On Friday, the Pentagon responded, "Russia has recently launched a concentrated disinformation campaign to discredit the United States and international partners and allies... Specifically, Russia has suggested that as a pretext for United States strikes against the Assad regime, humanitarian organizations in Syria were planning a chemical weapon attack. This is absurd," Pentagon spokesperson, Cmdr. Sean Robertson said.