The U.S., UK and France jointly launched strikes Friday night targeting the Assad regime’s chemical weapons capabilities after a suspected chemical attack killed dozens outside of Damascus, U.S. President Donald Trump announced.

“Today, the nations of Britain, France and the United States of America have marshaled their righteous power against barbarism and brutality,” Trump said from the Diplomatic Reception Room in the White House in nationally-televised remarks.

Trump said the U.S. is prepared “to sustain” the military assault “until the Syrian regime stops its use of prohibited chemical agents”, saying the joint response will also include economic and diplomatic components.

The three countries jointly launched strikes targeting the Assad regime’s chemical weapons research centre near Damascus, a chemical weapons warehouse and a command centre related to chemical weapons located in western Homs, U.S. Joint Chiefs of Staff Chairman Joseph Dunford said at a joint press conference with Secretary of Defense James Mattis.

Earlier Friday, the U.S. announced it has “very high confidence” that the Assad regime is responsible for a suspected chemical attack last weekend.

The White Helmets, a civil defense agency, blamed the Assad regime for the alleged chemical attack, which it said killed 78 civilians and injured hundreds of others.

In a statement following the attacks, the White House said “a significant body of information” points to the regime’s use of chlorine in the attack, and unspecified other information indicates it also used the nerve agent sarin.

“The evil and the despicable attack left mothers and fathers, infants and children thrashing in pain and gasping for air. These are not the actions of a man; they are crimes of a monster instead,” Trump said.

Addressing Bashar al-Assad’s principal allies, Iran and Russia, the president asked: “What kind of a nation wants to be associated with the mass murder of innocent men, women and children?”

“The nations of the world can be judged by the friends they keep,” Trump said.

The Organization for the Prohibition of Chemical Weapons (OPCW) has dispatched a fact-finding team to Syria that was expected to begin work Saturday before the strikes took place. If it continues as originally planned, the OPCW’s mission will be focused on determining whether a chemical attack took place but will not work to determine culpability.

Trump’s decision to carry out military action follows through on days of ratcheted tensions after the attack in Douma.

Earlier this week, Trump warned Russia that U.S. missiles “will be coming, nice and new and ‘smart!’” in response to the attack.

Friday night’s strikes are the second time Trump has ordered the U.S. military to target Syrian regime positions in response to a chemical attack. Last year, the U.S. targeted the Shayrat Airbase after a chemical attack blamed on the regime struck a town in northern Syria.

Announcing the attacks from Britain, UK Prime Minister Theresa May said the Assad regime’s “persistent pattern of behavior must be stopped – not just to protect innocent people in Syria from the horrific deaths and casualties caused by chemical weapons, but also because we cannot allow the erosion of the international norm that prevents the use of these weapons”.

“We have sought to use every possible diplomatic channel to achieve this, but our efforts have been repeatedly thwarted. Even this week, the Russians vetoed a resolution at the UN Security Council which would have established an independent investigation into the Douma attack,” the prime minister said.

Tuesday’s veto was Russia’s twelfth of council resolutions seeking to hold the Assad regime accountable for rights violations. Six of those resolutions sought to hold the regime accountable for chemical weapons attacks.

Anatoly Antonov, the Russian ambassador to the U.S., lashed out against the attacks, saying in a statement “a pre-designed scenario is being implemented”.

“We warned that such actions will not be left without consequences. All responsibility for them rests with Washington, London and Paris,” Antonov said. “The U.S. – the possessor of the biggest arsenal of chemical weapons – has no moral right to blame other countries.”

•Anadolu Agency.