On Friday, U.S. Ambassador to the United Nations Nikki Haley said Trump was still considering his options.
Several explosions were heard in the capital of Damascus.
Russian Federation has been a staunch ally of Syrian President Bashar Assad's government and has helped turn the tide of war in his favour since entering the conflict in September 2015.
He had no immediate details on casualties.
"Syrian air defence blocks American, British, French aggression on Syria", the reports said.
Trump indicated the strikes would continue until the Syrian regime's use of chemical weapons ends.
Although Russia warned of a conflict with the USA, it has also called on all parties involved in Syria to refrain from actions that could destabilize the region. He called on Moscow to change course and join the West in seeking a more responsible regime in Damascus.
According to the statement, May described the attack as a "shocking and barbaric act which killed up to 75 people, including children, in the most appalling and inhumane way".
Following a sarin attack on Syrian civilians in the town of Khan Sheikhoun in April 2017, Trump ordered strikes on the Shayrat air base in Homs. The message left no room for the possibility that an attack will not happen, at all.
"America does not seek an indefinite presence in Syria, under no circumstances", Trump said in his eight-minute address.
Trump says he has asked US partners "to take greater responsibility for securing their home region, including contributing large amounts of money for the resources, equipment and all of the anti-ISIS effort". "The United States will be a partner and a friend".
"... We pray that God will bring comfort to those suffering in Syria", Trump concluded.
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Corbyn has also evoked memories of the Iraq War, when lawmakers approved joining in the face of strong public opposition . Ministers agreed that May should continue to work with the United States and France to come up with the right response.
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Washington and Paris say the chemical attack in Douma is a clear violation of the Chemical Weapons Convention (CWC), which Syria signed in 2013 as part of Russia-brokered deal to eliminate such arms.
The United States launched cruise missiles at Assad's armed forces past year after a similar gas attack.
Reaction split mostly along party lines to President Donald Trump's announcement that the USA had launched a "precision strike" on Syria Friday night in response to an alleged reported chemical weapons attack last weekend.
"To Iran and to Russian Federation, I ask, what kind of a nation wants to be associated with the mass murder of innocent men, women and children?"
Mr Macron warned France has "proof" that the Syrian government carried out the chemical attack.
Under United Nations rules, military force is allowed under just three conditions: legitimate self-defence, at the request of the country where it would occur, or in case of Security Council authorisation.
Trump is also offering prayers for the Middle East and for the United States.
Activists and aid groups say that dozens died in Saturday's airborne assault on Douma, the last rebel stronghold in eastern Ghouta, which has been subjected to intensive bombing by Syria's Russian-backed Assad regime. "It is Russian Federation alone that used its veto 12 times to protect the Assad regime".
Earlier in the day, Trump told reporters that he was having a very close look at the situation.
Trump spoke from the White House Friday night.
Mr Trump said the U.S. was not seeking an "indefinite presence" in Syria.
The President will meet with his national security team at the White House on Thursday for further discussions on the U.S. response.
In that strike, 59 Tomahawk cruise missiles were launched from the USS Ross and USS Porter in the Mediterranean.