The U.S., France and Britain launched military strikes on Saturday morning in Syria to punish Assad for an apparent chemical attack against civilians last week and to deter him from doing it again.
The US' keenness to strike stemmed from its charge that the Syrian government had attacked a rebel-held enclave within the country with chemical weapons, killing about 50 people, and the West says it draws the line at chemical weapons, whose use is banned in global law.
Directly taunting US President Donald Trump, Assad said the effectiveness of Russia's weapons in repelling the strike proved whose military was really "lagging behind". But he appeared to contradict that message when he said on Saturday that Western allies were prepared to "sustain" the military response if Syrian President Bashar al-Assad does not stop using prohibited chemical weapons.
President Donald Trump has expressed his intention to pull all USA forces out of Syria in the near future.
"We are prepared to sustain this pressure, if the Syrian regime is foolish enough to test our will", Haley said.
The three allies used ships, a submarine and warplanes to launch a barrage of 105 guided missiles towards three chemical weapons facilities in Syria, officials said, including a research center on the outskirts of Damascus.
Second target was a chemical weapons storage facility west of Homs believed to be primary storage location of the regimes sarin and precursor production equipment. He also called for attacks on Syria to cease.
An image provided by the Department of Defense and presented at the Pentagon briefing on Saturday showing the areas targeted in Syria by the US-led coalition.
"This is going to set the Syrian chemical weapons program back for years", McKenzie said.
Western powers blamed President Bashar al-Assad, but Syria and its ally Russian Federation categorically denied the claims and accused the West of "fabricating" the incident to justify military action.
Several missiles hit a research centre in Barzeh, north of Damascus, "destroying a building that included scientific labs and a training centre", SANA reported.
Seven SCALP missiles hit the bunker, according to the U.S. military. "And we can not wait to alleviate further humanitarian suffering caused by chemical weapons attacks".
In 2013, he said, "we should stay the hell out of Syria" and "Let the Arab League take care of Syria".