WASHINGTON/BEIRUT • US President Donald Trump warned Russia of imminent military action in Syria over a suspected poison gas attack, declaring that missiles "will be coming", and lambasting Moscow for standing by Syrian President Bashar al-Assad.
"Russia vows to shoot down any and all missiles fired at Syria. Get ready Russia, because they will be coming, nice and new and 'smart!'," Mr Trump tweeted yesterday.
"You shouldn't be partners with a Gas Killing Animal who kills his people and enjoys it!" Mr Trump tweeted, referring to Moscow's alliance with Mr Assad.
Mr Trump was reacting to a warning from Russia on Tuesday that any US missiles fired at Syria over the deadly assault on a rebel enclave would be shot down and the launch sites targeted.
In response, Russia's Foreign Ministry said in a Facebook post that "smart missiles should fly towards terrorists, not towards the lawful government".
Foreign Ministry spokesman Maria Zakharova said any US missile strike could be an attempt to destroy evidence of the reported gas attack in the Syrian town of Douma, for which Damascus and Moscow have denied any responsibility.
In Damascus, the Foreign Ministry accused the United States, which has supported some rebel groups in the Syrian civil war, of using "fabrications and lies" as an excuse to hit its territory.
After the Douma attack, the insurgent group that had dug in there - Jaish al-Islam - finally agreed to withdraw. That sealed a major victory for Mr Assad in the war, crushing a protracted rebellion in the eastern Ghouta region near the capital Damascus.
The US Defence Department said it "does not comment on potential future military actions".
The World Health Organisation said yesterday that 43 people had died in Saturday's attack on Douma from "symptoms consistent with exposure to highly toxic chemicals", and more than 500 in all had been treated.
Moscow's threat to down US missiles came from its Ambassador to Lebanon, Mr Alexander Zasypkin, who said he was referring to a statement by President Vladimir Putin and the Russian armed forces chief of staff.
His remarks raised fears of direct conflict for the first time between major powers backing opposing sides in Syria's protracted civil war.
Russia is Mr Assad's most powerful ally, and its devastating air power has helped him wrest back large areas of territory from rebels since 2015. Both Russia and Iran, Mr Assad's other main ally, have warned his enemies against military action in recent days.
Moscow and Washington stymied attempts by each other at the United Nations Security Council on Tuesday to set up international investigations into chemical weapons attacks in Syria.
The US relationship with Russia is "worse now than it has ever been, and that includes the Cold War," Mr Trump tweeted yesterday.
The US President had cancelled on Tuesday a planned trip to Latin America later this week to focus instead on talks with Western allies about possible military action to punish Mr Assad.
Any US strike is likely to involve the navy, given the risk to aircraft from Russian and Syrian air defence systems. A US Navy guided-missile destroyer, the USS Donald Cook, is in the Mediterranean.
With tensions growing, pan-European air traffic control agency Eurocontrol warned airlines to exercise caution in the eastern Mediterranean due to the possible launch of air strikes into Syria over the next 72 hours.
Eurocontrol said that air-to-ground and cruise missiles could be used within that period, and there could be intermittent disruptions of radio navigation equipment.
Last year, the US carried out strikes from two navy destroyers against a Syrian air base after another toxic gas attack on a rebel-controlled area.