Donald Trump’s tweeted bluster that Russia should “get ready” for American missiles to hit Syria has outpaced a crucial U.S. ally’s current decisionmaking on military action against Damascus, The Daily Beast has learned.

Ever since Bashar Assad’s latest alleged chemical attack in Syria on Saturday, the U.S., France and Britain have scrambled to cobble together a concerted response. Russia, Assad’s patron, is taking a harsher stance against their anticipated strikes— substantially raising the prospect of a much larger conflagration between nuclear powers—which apparently prompted Trump to tap out a bellicose tweet telegraphing an imminent attack.

But that response in now ahead of where Trump’s allies are. A British diplomat familiar with the ongoing discussions on Syria told The Daily Beast on Wednesday that London had yet to decide on military action. That decision would come in response to a request from the U.K.’s allies. As of midday Wednesday, no such request had been made. The United States has not officially asked the United Kingdom for assistance in a Syria attack.

Trump’s Wednesday morning outburst on Twitter, a bit before 7:00 AM, came after reports that a senior Russian diplomat told a Hezbollah-run Lebanese TV station that Russia would blunt any U.S. strike on Syria. “The missiles will be downed and even the sources from which the missiles were fired,” said Alexander Zasypkin, Moscow’s ambassador to Lebanon, implying that Russia would attack U.S. Navy ships in the eastern Mediterranean, the likely source of cruise missile launches.

“ Trump’s tweeted warning also served as advance confirmation to Russia and Syria of imminent military action, something Trump has repeatedly criticized as foolhardy. ”

Zasypkin’s comments raised the stakes for a U.S. military strike of dubious legality to avenge the apparent chemical attack on the Douma suburb of Damascus. They came after Russia vetoed a United Nations Security Council resolution to investigate the Douma incident that left more than 70 people dead and 500 seemingly exposed to toxic chemicals.

And it was a signaled departure from the Russian response to the American military’s 2017 strikes on its ally in Damascus. Back then, Putin spokesman Dmitry Peskov called the cruise-missile attacks “a significant blow to Russian-American relations, which were already in a sorry state,” but took no further action.

Yet Trump appeared to take the threatened missile interception as a dare. “Get ready Russia, because they will be coming, nice and new and ‘smart!’” he tweeted.

The Pentagon declined comment on “potential future military actions,” spokesperson Lt. Cmdr. Rebecca Rebarich said, and referred comment to the White House “to characterize the president’s tweet,” but said the “horrifying” Douma attack “demands an immediate response from the international community.” A Central Command spokesperson, Maj. Josh Jacques, declined comment.

But James Mattis, Trump’s defense secretary, indicated Wednesday morning that an attack might not be imminent. "We stand ready to provide military options if they’re appropriate as the president determines,” Mattis said during a Pentagon visit with the Dutch defense minister. Mattis reportedly is meeting this afternoon at the White House to discuss Syria with Trump.

Matters were not clearer on Capitol Hill. “You never know what you’re dealing with with this guy,” said a senior congressional aide who requested anonymity while attempting to sort out whether Trump’s tweet portended actual military action.

Trump’s tweet was perhaps the most confrontational statement to the Russians in a presidency hitherto conspicuous for its solicitousness toward Moscow—whose interaction with Trump and his presidential campaign is the subject, of course, of a special counsel investigation overhanging the White House. (Following on his missile bluster, Trump even tried to blame the investigation for poisoned relations with Vladimir Putin.)

But Trump’s tweeted warning also served as advance confirmation to Russia and Syria of imminent military action, something Trump has repeatedly criticized as foolhardy.

“I don’t want to be one of these guys that say, yes, here’s what we’re going to do. I don’t have to do that,” he told reporters in February last year, a mantra he has repeated many times. “I don’t have to tell you what I’m going to do in North Korea, and I don’t have to tell you what I’m going to do with Iran. You know why? Because they shouldn’t know …”

White House officials did not respond to a request to explain the about-face.

This was, in point of fact, the second time that Trump gave advance warning to Russia about a contemplated attack on Assad regime military facilities. In April 2017, ahead of a 59 Tomahawk missile fusillade on the Shayrat airfield, U.S. officials notified Russian forces that an attack was imminent and “took precautions to minimize risk to Russian or Syrian personnel.”

This time, however, the Russians showed signs of confrontation. In addition to threatening U.S. warships, Moscow announced that it would send troops to Douma—right as the Organization for the Prevention of Chemical Weapons said it would seek to investigate the purported chemical weapons use on the ground. The Russian troops’ announced arrival occurs as Russia also said that thousands of civilians were evacuating Douma.

“ It sounds as if this Russian official were daring the U.S. to blind Russia's missile-launch early-warning system at the time of a coalition strike. Not sure he's thought this through. ” — François Heisbourg

For the past four days, Washington, London, and Paris have liaised to coordinate a united but as-yet-unspecified response. But the three did not appear on Tuesday night to have crossed the threshold of a decision to attack. The French president, Emmanuel Macron, tweeted on Tuesday that France was exchanging information with allies “to define our reaction,” set to arrive “in the coming days.” And some French defense analysts believe—or hope—that the Russian ambassador to Lebanon was getting ahead of himself and his government with the implicit threat to hit U.S. warships.

It “sounds as if this Russian official were daring the U.S. to blind Russia's missile-launch early-warning system at the time of a coalition strike,” said one of France’s most influential foreign policy analysts, François Heisbourg. “Not sure he's thought this through,” Heisbourg tweeted.

“Trump is now taunting the Russians,” Heisbourg told The Daily Beast. “It was a very unwise thing for Trump to respond, essentially, to a nobody.” Heisbourg speculated Trump may have been reacting a Fox News report about the Russian ambassador to Lebanon’s remarks, and added in English, “War in the era of Trump is going to be very hairy.”

But at the end of the day, Heisbourg thinks France will go ahead with military action alongside the United States. “I would expect that the whole thing will go forward notwithstanding [Trump’s imprudent tweet].”

French President Macron, who has cultivated close relations with Trump and has drawn his own red lines against chemical weapons in Syria, has the executive authority to push ahead with a coordinated attack.

But Britain’s prime minister, Theresa May, in most cases has to get authorization for military action from the House of Commons, though it is not clear she would necessarily need to in response to an allied request. As The Guardian pointed out Wednesday, that may be much more difficult after Trump’s bellicose preview of the U.S. led attack. A phone call between May and Trump on Tuesday resulted in an accord that the two would “continue working closely together and with international partners to ensure that those responsible were held to account,” according to a Downing Street readout.

In the first big showdown with Syria over chemical weapons, in 2013, when the Obama administration was getting ready to lead punitive attacks on Assad’s forces, the administration thought it could count on French and British support. But the House of Commons voted down London’s involvement, and that led to Obama retrenching as well.

A U.K. official told The Daily Beast that London and its allies were “rapidly reaching an understanding of this shocking and barbaric incident” in Douma. The official said the U.K. was in “close touch with our allies and remain so to ensure a strong, united international response” – something Trump’s tweets appeared to jeopardize.