She said Russian Federation would ensure the monitors' security.
"I have no reason to believe that that's going to happen", Ryan said at a news conference.
And in a further sign of escalating tensions last night Russian military chiefs vowed to send troops to Douma over the coming days. He said Assad's forcers should then push east of the Euphrates River, where US troops are embedded with Kurdish forces. "We have already learnt how to do it and will definitely turn all these actions to the benefit of our own economy and economic development", he said, warning "but we will not forget those who continue this anti-Russian policy, those who harm our country".
Signalling that a US-led military attack is imminent, the president promised that the bombs "will be coming, nice and new and smart".
Activists, local rescuers, and rebels in Syria claim that Syrian government forces used chlorine gas on Saturday in an attack in Douma, a rebel-held area near capital Damascus.
And, even if Twitter had an unlimited character count, is a microblogging site really the proper medium on which to announce military action against a foreign power while taunting another foreign power about it?
One official said the U.S., France and Britain were considering military options that would be more extensive than the punitive, one-day strike last April.
Russian Federation doesn't have the financial capability to retaliate to a military intervention in Syria by the US. On Tuesday, Macron said any French action would target Syria's chemical weapons abilities.
The attack comes nearly a year after a chemical attack in the northern Syrian town of Khan Sheikhoun killed dozens of people.
A Kremlin spokesman has said claims of a chemical weapons attack were fabricated.
US President Donald Trump welcomes the Emir of Qatar Sheikh Hamad Khalifa Al-Thani (not pictured) at the White House in Washington, April 10, 2018.
The sending of the nuclear aircraft carrier Harry S. Truman to the region would increase USA striking power, but also gave United States policymakers more time to consider and plan their options, Kwiatkowski observed. Dmitry Peskov added that it would have an "utterly destructive impact on the Syrian settlement".
The US has recruited support from Britain, France, Saudi Arabia and Qatar for military action, but with the exception of Paris, it is unclear what allies will join the US in an operation created to dissuade the Assad regime from carrying out chemical attacks.
On Thursday, President Donald Trump sent a Twitter message stating that a USA missile attack on Syria in retaliation for an alleged chemical attack in the city of Duma on April 7 could come very soon or significantly later. It was not immediately clear whether that visit would delay or avert USA or allied military action.
Turkish President Recep Tayyip Erdogan says he will discuss ways of ending "the chemical massacre" in Syria during a telephone call with Russia's President Vladimir Putin.
Erdogan's remarks appear to criticize an exchange of threats by the United States and Russian Federation, saying Turkey was "deeply disturbed by some countries that rely on their military might, turning Syria into a virtual wrestling ground". "Get ready Russian Federation, because they will be coming", adding his disapproval of Moscow's support of Syrian President Bashar al-Assad.
Russia, meanwhile, has vowed to respond to any US action targeting the Assad government. "This kind of targeting is consistent with the former (and possibly present) neoconservative objective, once criticized by Trump, of unseating or destroying the Assad regime", she said.
He also urged the Israeli PM to refrain from any moves that would further destabilize the situation in the Arab country and endanger its security.