Its foreign ministry said: "The Syrian Arab Republic condemns in the strongest terms the brutal American-British-French aggression against Syria, which constitutes a flagrant violation of global law". Anatoly Antonov, Russian Ambassador to the USA, issued a response on the embassy's Facebook page.

President Trump on Saturday touted the "perfectly executed strike" against the Assad regime in Syria, thanking France and Britain for joining the US-led assault before declaring "Mission Accomplished!". "So, I ordered the French armed forces to intervene tonight, as part of an worldwide operation in coalition with the United States of America and the United Kingdom and directed against the clandestine chemical arsenal of the Syrian regime".

Trump also took a swipe at Russian Federation and Iran, condemning their continued support to Assad's regime.

The strikes were conducted by the USA, the United Kingdom and France following a suspected chemical attack on the town of Douma, which left an estimated 70 people dead.

Trump said that he made a decision to take action because last weekend's action by Bashar Al-Assad "was a significant attack against his own people", and "not the actions of a man, they are crimes of a monster instead".

Witnesses told CNN that they heard explosions in the capital city of Damascus and that they began while Trump was making his address.

At a Pentagon briefing, Chairman of the Joint Chiefs of Staff General Joseph Dunford said the targets included a Syrian research facility and a chemical weapons storage facility.

The US and its allies fired more than 100 cruise missiles at Syria, a significant number of which were intercepted by Syrian air defences, the Russian defence ministry said on Saturday.

May has repeatedly said that the missile strike on Syria was not about "regime change". Numerous conservative commentators have lambasted the president for breaking one of his main campaign promises of not participating in military intervention in the Middle East. Thousands of people are also retweeting some of Trump's previous comments warning against military action in Syria.

Jaish al-Islam has said it only agreed to the deal because of the Syrian government's purported use of toxic chemicals on Douma, which medics said killed more than 40 people. According to reports, after determining that Assad's government used sarin gas on citizens, United States had attacked Syria. A USA official told Reuters that Tomahawk cruise missiles also were involved.

More than 100 missiles were fired in the capital city of Damascus by the USA and its allies- France and Britain. All the missiles hit their targets around 4 a.m. local time, McKenzie said.

The operation was "precise, overwhelming and effective", he said, adding it will set their chemical weapons program back "for years".

Russia's ambassador to the U.S. warned that there would be consequences for the US-led military strikes, adding that it was not acceptable to insult Russia's president.

"What kind of a nation wants to be associated with the mass murder of innocent men, women and children?"

British Prime Minister Theresa May won backing from her senior ministers on Thursday to take unspecified action with the United States and France to deter further use of chemical weapons by Syria. She described it as a "limited and targeted strike" aimed at minimizing civilian casualties.

House Speaker Paul Ryan is praising Trump's "decisive action in coordination with our allies", adding, "We are united in our resolve".

Other strikes targeted an army depot near Homs. At the time, the Pentagon claimed that a fifth of Syria's operational aircraft were either damaged or destroyed.

The strikes came a week after an alleged gas attack that killed more than 40 people outside Damascus, but which Syria said was a "fabrication" meant to justify military action.

"Syria continues to engage in and provide a base for murderous actions, including those of Iran, that put its territory, its forces and its leadership at risk", an Israeli official told NBC News. He criticized the US and its allies for launching the strike without waiting for inspectors from the global chemical weapons watchdog to visit the area.