A day after warning Russia in a tweet that “missiles will be coming” to Syria, President Trump said on Twitter that an airstrike was not necessarily imminent.

“Never said when an attack on Syria would take place,” Trump tweeted early Thursday. “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?’”

Trump has been weighing U.S. military options in Syria in the wake of Saturday’s chemical attack that killed at least 40 people. Syrian President Bashar Assad is suspected to have ordered the attack as part of an ongoing war against both the Islamic State group and various antigovernment forces. According to the U.N. envoy for Syria, an estimated 400,000 Syrians have been killed since 2011.

Defense Secretary James Mattis said Wednesday that the U.S. and its allies are mulling how to respond to the attack.

“We are still assessing the intelligence, ourselves and our allies,” Mattis said. “We’re still working on this.”

But Trump’s early morning tweet Wednesday suggested U.S. military action was inevitable.

“Russia vows to shoot down any and all missiles fired at Syria,” Trump wrote on Twitter. “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 tweet was criticized by some lawmakers and military analysts who questioned the wisdom of the president publicly telegraphing his move — something Trump denounced former President Barack Obama for doing.

President Trump speaks during a meeting with senior military leaders at the White House in Washington, D.C., on Monday. At right is new national security adviser John Bolton. (Photo: Nicholas Kamm/AFP/Getty Images)

On Thursday, Trump also pushed back against a New York Times report that he “sought to fire” special counsel Robert S. Mueller, who is leading the federal investigation into Russian meddling in the 2016 presidential election.

“If I wanted to fire Robert Mueller in December, as reported by the Failing New York Times, I would have fired him,” Trump tweeted. “Just more Fake News from a biased newspaper!”

Story continues

Trump has made no secret about his hostility toward Mueller in recent days. Trump has repeatedly assailed Mueller’s probe as “corrupt” and “fake,” while suggesting that it is responsible for “much of the bad blood with Russia.” He has also attacked the former FBI chief as “conflicted.”

Earlier this year, the Times reported that Trump ordered Mueller’s firing last June but “ultimately backed down” after White House counsel Donald F. McGahn II threatened to resign in protest.

This week, CNN reported that Trump is considering firing Deputy Attorney General Rod Rosenstein, who oversees Mueller, after the FBI raided the office and hotel of Trump’s longtime lawyer, Michael Cohen. Federal agents were reportedly looking for information related to Cohen’s hush-money payment to porn star Stormy Daniels on the eve of the 2016 presidential election, as well as any information related to the “Access Hollywood” tape on which Trump brags on a hot mic about sexually assaulting women.

Trump called the raid a “a total witch hunt.”

“It’s a disgraceful situation,” Trump told reporters before a meeting of military officials at the White House on Monday night. “It’s an attack on our country, in a true sense. It’s an attack on what we all stand for.”

Read more from Yahoo News:

(Cover photo credit: Photo illustration: Yahoo News; photos: Mouneb Taim/Anadolu Agency/Getty Images, Ted Aljibe/AFP/Getty ImagesNicholas Kamm/AFP/Getty Images)