US Secretary of State Rex Tillerson said there was “no doubt” that the Syrian government was responsible for the attacks, which killed more than 80 people, some of them children.
Speaking on board Air Force One, President Donald Trump appeared to call for aAssad to step down after the attack.
He said that what happened in Syria is “a disgrace to humanity.” Asked if Assad should go, Trump said, “He’s there, and I guess he’s running things so something should happen.”
Meanwhile, even key ally Russia said its support for the Assad government was not unconditional.
Turkey said samples from victims of Tuesday’s attack on the northern opposition-held town of Khan Sheikhoun indicate they were exposed to sarin, a highly toxic nerve agent.
Syria rejected the accusations, and Moscow warned against apportioning blame until an investigation had been carried out.
The Pentagon was last night presenting options to President Donald Trump over possible military action in the region, including the possible creation of “safe zones”, which Tillerson said was under discussion with other world leaders.
He said:” There is no doubt in our minds that Syria and its leadership are responsible for these attacks. Furthermore, it is very important that the Russian government considers very carefully their support.”
Discussions continued last night at UN headquarters on a Security Council resolution that would condemn the chemical attack.
Kremlin spokesman Dmitry Peskov said that “unconditional support is not possible in this current world.” He added: “It is not correct to say that Moscow can convince Mr Assad to do whatever is wanted in Moscow. This is totally wrong.”
Russia has provided military support for the Syrian government since September 2015, turning the balance of power in Assad’s favor. Moscow has used its veto power at the Security Council on several occasions since the civil war began six years ago to prevent sanctions against Damascus.
The two countries “enjoy a relationship of cooperation, of exchange of views and full mutual support,” said Peskov, a spokesman for President Vladimir Putin. Assad and his army are “the only real power in Syria that can resist terrorists on the ground,” he said.
The Syrian government maintains it did not use chemical weapons, instead blaming opposition fighters for stockpiling the chemicals. Russia’s Defence Ministry said the toxic agents were released when a Syrian airstrike hit a rebel chemical weapons arsenal and munitions factory on the eastern outskirts of the town of Khan Sheikhoun.
“I stress, once again, that the Syrian Arab Army did not and will not use such weapons even against the terrorists who are targeting our people,” Syria’s Foreign Minister Walid Moallem said in Damascus.
German Foreign Minister Sigmar Gabriel welcomed Trump’s strong condemnation, but warned against a military escalation.
French Foreign Minister Jean-Marc Ayrault urged a resumption of Syrian peace talks and said he wants Assad’s government prosecuted over its alleged use of chemical weapons.