Washington (CNN) President Donald Trump warned Russia on Wednesday that it should "get ready" for a missile strike on Syria, vowing to thwart any missile defenses.

"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!'," Trump wrote. "You shouldn't be partners with a Gas Killing Animal who kills his people and enjoys it!"

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! — Donald J. Trump (@realDonaldTrump) April 11, 2018

The public suggestion of US military confrontation with Russia is sure to raise tensions in an already volatile situation and add more confusion to US policy in the region. Trump said earlier this month -- before the weekend's suspected chemical attack on civilians at the hands of the Assad regime -- that he wanted to withdraw US troops from Syria. Wednesday's statement is also notable because Trump has criticized his predecessors for publicly telegraphing US military action.

Trump appeared to soften his rhetoric in a follow-up tweet Wednesday morning, saying there is "no reason" for the US's worsening relationship with Russia and that "we need all nations to work together. Stop the arms race?"

Our relationship with Russia is worse now than it has ever been, and that includes the Cold War. There is no reason for this. Russia needs us to help with their economy, something that would be very easy to do, and we need all nations to work together. Stop the arms race? — Donald J. Trump (@realDonaldTrump) April 11, 2018

Trump also conflated US tensions with Russia over special counsel Robert Mueller's probe, saying "much of the bad blood with Russia is caused by the Fake & Corrupt Russia Investigation."

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