Northwestern University global relations specialist Ian Hurd said the president's tweet is a simple play to his domestic political base, and that after last year's US missile attack over similar chemical weapons concerns, the president has to be seen to be doing something now. He called for a "strong and joint response" to the attack in the Syrian town of Douma on Saturday, which Syrian activists and rescuers say killed 40 people.
US Ambassador Nikki Haley said no decision had been taken to launch strikes and stressed Washington was taking time to assess the implications of possible military action after Russia warned it could lead to a unsafe US-Russian war.
A separate YouGov survey on Thursday found 61 percent of people think it would be necessary for parliament to vote on military action against Syria, with just 18 percent saying it was not necessary and 21 percent undecided.
Vladimir Shamanov, a former commander-in-chief of the Russian Airborne Troops, also vowed that Russia would take all political, diplomatic and military retaliatory measures if the U.S. carried out any attacks in Syria. "Those are contradictory goals".
Lavrov noted that Russian and US militaries have a hotline to prevent incidents, adding that it's not clear if it would be sufficient amid mounting tensions.
Defense Secretary Jim Mattis was not seen publicly Friday, but he is known to argue for ensuring that military action in any context is linked to a broader political strategy.
A auto with loudspeakers blaring the national song "Oh Syria, You Are My Love" could be heard driving through central Damascus amid the attack.
A strike against Syria will likely come in the form of missiles, as was the case a year ago. It was one of the least lethal responses considered.
Konashenkov released statements by medics from Douma's hospital, who said a group of people toting video cameras entered the hospital, shouting that its patients were struck with chemical weapons, dousing them with water and causing panic.
Mattis said he personally believes Syria is guilty of an "inexcusable" use of chemical weapons, while noting that the worldwide fact-finding team would likely fall short of determining who was responsible. A Navy destroyer, the USS Donald Cook, was underway in the eastern Mediterranean.
The White House says President Donald Trump has decided not to attend a summit in South America this week to remain in the U.S.to manage the crisis.
Rafah al-Okda, a 21-year-old nursing student at Damascus University, said she had not changed her routine following the threats.
Last year, the USA military formally notified Russian Federation over a hotline shortly before 59 Tomahawk cruise missiles struck the Shayrat air base. Assad did not respond.
President Trump extended his uncharacteristic attack on Russian Federation, saying the US's relationship with Moscow was worse than ever, suggesting it needs American help with its economy. The U.S. goal was to minimize risk to Russian or Syrian personnel.
The 2,000 USA troops in Syria advising local forces on defeating Islamic State militants would be vulnerable to missiles, artillery and other attacks, the former official said.
The attack began at 4 a.m. (0100 GMT) with missiles hitting the eastern suburbs of Damascus, shaking the grounds from a distance.
Former President Barack Obama declared that the use of chemical weapons would be a red line that would prompt the United States' intervention. Those systems encircle Damascus and some of Syria's larger bases.
After May met with her Cabinet, a spokesperson issued a statement saying it is highly likely that Syria's President Bashar Assad was responsible for Saturday's attack that killed dozens outside Damascus. He, like Thompson, anxious about the Russian reaction.
Ryanair, British Airways, Etihad Airways, and Royal Jordanian representatives said flights were operating normally at their respective airlines, but the situation was being monitored closely.