President Donald Trump has warned Syria’s government the US is “locked and loaded” to strike again if it carries out new chemical attacks.
The warning came after the US, UK and France struck three Syrian sites in response to a suspected deadly chemical attack in the town of Douma a week ago.
Syria denies any chemical use and says that attack was fabricated by rebels.
A UN Security Council vote brought by Syria’s ally, Russia, and condemning the US-led strikes was rejected.
The wave of strikes represents the most significant attack against President Bashar al-Assad’s government by Western powers in seven years of Syria’s civil war.
US envoy Nikki Haley said the strikes were “justified, legitimate and proportionate”.
She said: “I spoke to the president this morning and he said, ‘if the Syrian regime uses this poisonous gas again, the United States is locked and loaded’.”
She added: “When our president draws a red line, our president enforces the red line.”
Ms Haley said the US and its allies had given diplomacy “chance after chance” but Russia had continued to veto UN resolutions.
She said: “We cannot stand by and let Russia trash every international norm and allow use of chemical weapons to go unanswered.”