President Donald Trump on Thursday denounced Syria's Bashar al-Assad as responsible for a "terrible," "egregious" crime, suggesting the United States could be poised to take action over this week's suspected chemical attack.

"What Assad did is terrible. What happened in Syria is truly one of the egregious crimes," Trump said while travelling to Florida on board Air Force One. 

"I think what happened in Syria is a disgrace to humanity, and he's there, and I guess he's running things, so I guess something should happen."