In the aftermath of a suspected chemical weapons attack in the Damascus suburb of Douma that killed more than 40 people and sickened 500 on Saturday, President Trump has directly blamed the devastation on lethal gas used by Syrian President Bashar Assad. Mr. Trump threatened a response involving "smart" weaponry and suggested it was all coming "very quickly."

These are conclusions and details his military and intelligence leaders have been reluctant to confirm, let alone repeat. Their caution suggests the president may be speaking out about military strategies using a current, but so far incomplete, information set. He is also – apparently uncharacteristically – communicating at least one intended military action in a way he has previously said any leader would be foolish to do.

On Sunday, soon after reports of the attack first emerged, Mr. Trump tweeted, "Many dead, including women and children, in mindless CHEMICAL attack in Syria," and criticizing Russia and Iran, both of which are allied with Assad's government in the seven-year conflict, for, as he put it, "backing Animal Assad."

In an additional series of tweets on Wednesday morning, the president suggested the U.S. was preparing for a missile attack on Syria and said, "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!"

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But later on Wednesday, White House press secretary Sarah Sanders said repeatedly the president was considering "a number" of options that potentially included missile strikes. "All of those options are still on the table," Sanders said. "Final decisions haven't been made yet on that front," she said, and that no timeline for any strikes had been established.

Russia and the Assad government have said there was no evidence that the alleged gas attack took place but, Sanders said "the intelligence provided certainly paints a different picture, and the President holds Syria and Russia responsible for this chemical weapons attack."

Public reports do strongly suggest chemical weapons were used by the Syrian government forces, which currently surround Douma. In a joint statement, the Syrian Civil Defense (White Helmets) and Syrian American Medical Society have said victims of the attack exhibited, "symptoms indicative of exposure to a chemical agent."

Western allies have been publicly sanguine about the need for a military response, but have said they should be contingent on conclusive intelligence assessments. British Prime Minister Theresa May has said she supports swift retaliation "if" the Assad regime is found responsible for the attack, adding that "all the indications" are that it is. A French readout of a call between Mr. Trump and Macron condemned the use of chemical weapons while stating evidence-gathering and information-sharing would continue. (An American readout said, "both leaders strongly condemned the horrific chemical weapons attacks in Syria and agreed that the Assad regime must be held accountable for its continued human rights abuses.")

Hours after the president issued his tweet on missile strikes, Secretary of Defense James Mattis avoided directly attributing or otherwise characterizing a chemical weapons attack. "We're still assessing the intelligence ourselves and our allies," he said, "We're still working on this."

"Certainly there are things that are being assessed," Sanders said, when asked about Mattis' remarks later on Wednesday. "But we're confident in the part of this process that we're in to feel comfortable making the assertions that we have earlier today."

The intelligence community has indicated Mr. Trump is fully briefed on the latest developments in Syria, but has also not yet said conclusively what the type or provenance of the weapons was.

"The Intelligence Community has been fully engaged in assessing the reported chemical weapons attack in Syria on Saturday," Brian Hale, a spokesman for the Office of the Director of National Intelligence, told CBS News. "Director Coats and other senior IC leaders are working to ensure all IC elements are providing the most current and comprehensive intelligence assessments to the president and his national security team."

The Kremlin, meanwhile, has dismissed Mr. Trump's tweets as unserious. "We do not participate in Twitter diplomacy," said spokesman Dmitry Peskov, according to the Interfax news agency. "We support serious approaches. We continue to believe that it is important not to take steps that could harm an already fragile situation."

The Pentagon has indicated, however, that it will be ready if and when the President decides to take action.

"We stand ready to provide military options if they're appropriate, as the president determined," Mattis said Wednesday.