Syrian leader Bashar al-Assad should have no role in a future Syria, US Secretary of State Rex Tillerson says.
Signalling a shift in US policy, he called for “a political process that would lead to Assad leaving”.
His remarks follow a suspected chemical attack in Syria, which US President Donald Trump called a “disgrace to humanity”.
The US is said to be mulling possible military action in Syria, although it is unclear what that might entail.
Measures reported to be under discussion between the Pentagon and the White House are the grounding of Syrian warplanes and the setting up of safe zones for civilians.
Mr Tillerson’s comments signal an apparent U-turn for the US – only last week the US ambassador to the UN, Nikki Haley, said Washington was no longer prioritising the removal of President Assad.
Mr Tillerson had also said Mr Assad’s long-term future would “be decided by the Syrian people”.
But speaking in Florida on Thursday, Mr Tillerson said: “Assad’s role in the future is uncertain and with the acts that he has taken, it would seem that there would be no role for him to govern the Syrian people.
“We are considering an appropriate response (to the) violations of all previous UN resolutions, violations of international norms.”
He said “steps were underway” to organise an international coalition to remove Mr Assad.
Dozens of people, including at least 27 children, are reported to have died following an attack on the town of Khan Sheikhoun in Idlib province early on Tuesday.
Evidence has mounted that the victims were killed with a nerve agent such as Sarin.
Syria has denied dropping chemical weapons from the air and its key ally, Russia, had argued that the mass poisoning was caused by an air strike on a rebel weapons dump where chemical weapons were being stored.
But the claims have been viewed with scepticism from the US and its allies.
[BBC]