President Trump had a ready retort to a Russian threat to shoot down any U.S. missiles in Syria: “Get ready Russia, because they will be coming, nice and new and ‘smart!‘”

Trump tweeted that news early Wednesday and added, “You shouldn’t be partners with a Gas Killing Animal who kills his people and enjoys it!”

As NPR’s Mara Liasson reports, Trump’s warning of an international military strike contradicts his earlier criticism of President Obama’s actions in Syria.

“He’s doing exactly what he criticized Obama for doing,” Mara said on Morning Edition. “He said earlier this week, we’ll tell you what we do after the fact. He’s often said he doesn’t like to broadcast in advance what he would do, in terms of military strikes. But here he is taunting Putin, just like he did when he tweeted to Kim Jong Un — my button is bigger than yours.”

“So he’s doing the exact same thing that he criticized his predecessors for doing.”

Trump changed his tone in another tweet that was posted some 40 minutes later, calling for a better relationship with Russia.

“Our relationship with Russia is worse now than it has ever been, and that includes the Cold War,” Trump said. “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?”

Trump unleashed his counter-threat hours after Russia’s ambassador to Lebanon warned that his country will shoot down any U.S. missiles fired at Syria in a punitive strike on the Damascus regime over its alleged use of chemical weapons.

“If there is a strike by the Americans, then … the missiles will be downed and even the sources from which the missiles were fired,” Alexander Zasypkin told Hezbollah’s al-Manar TV Tuesday evening, speaking in Arabic, according to Reuters.

NPR’s Lama Al-Arian, reporting from Beirut, reports that Zaspykin said he was quoting Russian President Vladimir Putin. The threat applies not only to the missiles, but to their launch sites, she says.

However, Zaspykin said that a clash “should be ruled out” and that Russia was “ready to hold negotiations.”

His remarks follow Russia’s veto of a U.S. draft Security Council resolution calling for an independent investigation to establish with certainty if Syria used poison gas against civilians in Douma, a rebel-held suburb of Damascus, last week.

Syria has denied that it used poison gas.

President Trump on Tuesday warned the U.S. was prepared to take “forceful” action. “We have a lot of options, militarily,” he said.

Russia joined the Syrian civil war to fight alongside Assad in 2015. Although its Security Council veto was expected, Nikki Haley, the U.S. Ambassador to the United Nations, said Moscow’s decision to stand with its ally, Syrian President Bashar al-Assad, amounted to “protecting a monster over the lives of the Syrian people.”

Earlier, Russia’s U.N. envoy, Vassily Nebenzia cautioned the U.S. to “refrain from the plans that you’re currently developing,” saying Washington would “bear responsibility” for any “illegal military adventure.”

In a further sign that military action may be imminent, Eurocontrol, the European air-traffic control agency, issued a warning on Wednesday to commercial airliners flying in the eastern Mediterranean.

“Due to the possible launch of air strikes into Syria with air-to-ground and/or cruise missiles within the next 72 hours, and the possibility of intermittent disruption of radio navigation equipment, due consideration needs to be taken when planning flight operations in the Eastern Mediterranean/Nicosia FIR area,” it said, referring to the designated airspace, Reuters reports.

In the alleged poison gas attack in Douma on Saturday, pro-opposition rescue workers and doctors tell NPR’s Ruth Sherlock that 42 people were killed – the same number as reported by the Britain-based Syrian Observatory for Human Rights.

Doctors have said that the symptoms presented by suspected victims of the attack are consistent with chlorine gas. In the past, the U.S. and its Western allies have accused Syria of using Sarin gas against civilians, a charge Damascus denies.

Meanwhile, the Organization for the Prohibition of Chemical Weapons (OPCW) has said the Syrian and Russian governments have invited it to conduct a fact-finding mission on the ground in Syria to “establish facts surrounding the allegations of the use of toxic chemicals, reportedly chlorine, for hostile purposes in the Syrian Arab Republic.”

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