U.S. President Donald Trump announced the military action from the White House, saying the three allies had “marshalled their righteous power against barbarism and brutality.”
As he spoke, explosions rocked Damascus.
British Prime Minister Theresa May described the strike as “limited and targeted” and said she had authorized the British action after intelligence indicated Syrian President Bashar al-Assad’s government was responsible for an attack using chemical weapons in Douma last Saturday.
French President Emmanuel Macron said the strikes had been limited so far to Syria’s chemical weapons facilities.
With more than 100 missiles fired from ships and manned aircraft, the allies struck three of Syria’s main chemical weapons facilities, U.S. Defense Secretary Jim Mattis and Joint Chiefs of Staff Chairman General Joseph Dunford said.
The targets included a Syrian center in the greater Damascus area for the research, development, production and testing of chemical and biological weaponry as well as a chemical weapons storage facility near the city of Homs. A third target, also near Homs, contained both a chemical weapons equipment storage facility and a command post.
Mattis called the strikes a “one time shot,” but Trump raised the prospect of further strikes if Assad’s government again used chemical weapons.
“We are prepared to sustain this response until the Syrian regime stops its use of prohibited chemical agents,” the U.S. president said in a televised address.
The Syrian conflict pits a complex myriad of parties against each other, with Russia and Iran giving Assad military and political help while fractured opposition forces have had varying levels of support at different times from the West, Arab states and Turkey.
The strikes risked raising tensions in an already combustible region, but appeared designed not to trigger a military response from Russia and Iran.
Nevertheless, Assad’s government and Russia responded angrily.
“Again, we are being threatened. We warned that such actions will not be left without consequences,” Anatoly Antonov, Russia’s ambassador to the United States, said on Twitter.
Syrian state media said the attack would fail and called it a “flagrant violation of international law.”
Russia was likely to call for a meeting of the United Nations Security Council to discuss the air strikes, lawmaker Vladimir Dzhabarov, the deputy head of Russia’s foreign affairs committee, was quoted by the RIA news agency as saying.
The strikes seemed unlikely to have much impact on the balance of power in Syria’s seven-year-old civil war, in which Assad’s government has steadily gained the upper hand against armed opponents since Russia intervened in 2015.
In a statement issued by the Kremlin, the Russian leader said Moscow called for an emergency meeting of the United Nations' Security Council over the strike launched by the US, Britain and France.
Mr Putin added that the strike had a "destructive influence on the entire system of international relations".
He reaffirmed Russia's view that a purported chemical attack in the Syrian town of Douma that prompted the strike was a fake.
Mr Putin added that Russian military experts who inspected Douma found no trace of the attack.