U.S. President Donald Trump is considering eight targets in Syria for a potential retaliatory strike over the lethal chemical attack on the rebel-held town of Douma last week, which killed 40 people and injured hundreds.
Trump met with his national security team on Thursday to discuss the situation in Syria, but has not made a final decision on whether to use military force, White House Press Secretary Sarah Sanders said.
"We are continuing to assess intelligence and are engaged in conversations with our partners and allies," Sanders said in a statement.
CNBC reported that the U.S. is considering striking eight potential targets, including two Syrian airfields, a research center and a chemical weapons facility.
Syria's military has repositioned a significant number of air assets to Russian-controlled airfields in recent days, in the hope that Washington would be reluctant to strike there.
Over the past five days, Trump has sharpened his rhetoric against Syria and its ally Russia, and via Twitter issued a threat of a potential U.S. strike.
"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 president tweeted.
Trump's tweet prompted a slew of Russian warnings that a U.S. strike could trigger a direct military clash between the two superpowers.
A day later, Trump backpedaled his announcement and said that a U.S. missile strike on Syria may not be imminent.
"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?'" he tweeted.
Later the same day, he tweeted, "We're having a number of meetings today, we'll see what happens. Now we have to make some ... decisions, so they'll be made fairly soon."
The White House said a timeline for striking Syria has not been set, and that "all options are on the table."
The Pentagon released a statement saying, "The department does not comment on potential future military actions or specific military assets that might be associated with those actions."
The Syrian Foreign Ministry denounced Trump's threat to attack the country as "reckless," saying such belligerent rhetoric is "a danger to international peace and security."
U.S. military officials were reportedly frustrated by Trump's decision to confirm – and to do so on social media – the nature of the weapons that would be used in a potential strike on Syria.
"By telegraphing our punch so early, you give the Syrians the opportunity to harden themselves as a target and you give them the opportunity to have more time to think through what our potential response might be," said Christine Wormuth, who served as undersecretary of defense for policy in the Obama administration.
Wormuth said the early telegraphing of U.S. military actions also allows Syria, Russia and Iran to think about "how they in return might try to fight back against it."
Former U.S. Ambassador to NATO Nicholas Burns, who has advised Republican and Democratic presidents and is now a professor at Harvard's Kennedy School of Government, took Trump to task for taunting Russia about a possible missile strike on Syria.
"This is not a video game. The president of the United States needs to be calm and needs to act presidential," Burns told CNBC. "The tweet this morning was irresponsible. And it wasn't presidential. It wasn't effective."
Burns said the White House needs to separate any U.S. response in Syria from the American relationship with Russia.
"There's no question that the Russians are wrong to support the Syrian government. They are a real problem for us. But we're talking about airstrikes here," he said. "I will support the use of airstrikes against Syria, but you don't want to mix Russia into this. You don't want the Russians to think the United States is targeting them. I would separate the two issues."
