Amid speculation over an impending US missile strike on Syrian military assets, Donald Trump has tweeted that an American attack could come “very soon or not so soon at all”.
The US president said he “never said when an attack on Syria would take place.”
Mr Trump has said he will follow Israel in conducting an attack on the Syrian regime in response to a suspected chemical weapons attack on civilians in Douma, eastern Ghouta.
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He tweeted: “Never said when an attack on Syria would take place. Could be very soon or not so soon at all! In any event, the United States, under my Administration, has done a great job of ridding the region of Isis. Where is our ‘Thank you America?’”
Mr Trump previously warned Russia to “get ready,” saying missiles “will be coming.”
After Moscow threatened to shoot down any missiles fired at Syria, Mr Trump tweeted: “Russia vows to shoot down any and all missiles fired at Syria. Get ready Russia, because they will be coming, nice and new and “smart!” You shouldn’t be partners with a Gas Killing Animal who kills his people and enjoys it!”
The US defence secretary, James Mattis, said the US was assessing intelligence about the suspected gas attack.
Asked if he had seen enough evidence to blame the Syrian president, Bashar al-Assad, Mr Mattis said: “We’re still working on this.”
Both the Syria and Russia have said reports of the attack were fabricated by rebels and rescue workers in Douma.
They have accused the US of seeking to use it as a pretext to attack the regime.