President Donald Trump's administration is ratcheting up the pressure on Russia to stop backing Syrian dictator Bashar al-Assad in the wake of a gas attack that killed more than 80 civilians last week – and even floating the possibility that Vladimir Putin's regime was complicit in the carnage.
Washington's tough line with the Kremlin over the weekend suggests the U.S. missile strike against a Syrian air base last week marked a larger turn toward a confrontational approach to dealing with Mr. Putin.
The shift in tone could put Secretary of State Rex Tillerson on a collision course with the Russians when he is expected to visit Moscow on Wednesday, in the first major meeting between the Trump and Putin administrations. The sit-down between Mr. Trump's chief diplomat and his Russian counterpart will test the United States' ability to exert pressure on Moscow to drop its Syrian ally.
The souring in relations between Washington and Moscow marks a break from the President's campaign-trail rhetoric, in which he expressed admiration for the Russian leader. Moscow even interfered in the election in a bid to help Mr. Trump by hacking Democratic Party servers and releasing embarrassing e-mails – leading to persistent questions about contacts between members of Mr. Trump's circle and the Russian administration.
Nikki Haley, the U.S. ambassador to the United Nations, accused Russia Sunday of trying to "cover for Assad," and said Mr. Tillerson would demand answers from Moscow on why it failed to stop the attack.
"Either they knew that there were chemical weapons and they knew there was going to be chemical-weapon use and they just hid it from the international community, or they are being played for fools by Assad," she said on CNN's State of the Union.
Asked if Mr. Trump was considering slapping tougher sanctions on Russia, Ms. Haley said such moves are currently under consideration.
Mr. Tillerson, for his part, said he would press Russian Foreign Minister Sergey Lavrov on why Moscow had not fulfilled a 2013 agreement to ensure Syria's chemical weapons were rounded up and destroyed.
"The failure related to the recent strike and the recent terrible chemical-weapons attack, in large measure, was a failure on Russia's part to achieve its commitment to the international community," Mr. Tillerson said on ABC's This Week.
Russia has long backed Mr. al-Assad's efforts to hold on to power in Syria as several groups, from moderates to the Islamic State, have attempted to overthrow him. The intervention of Russian warplanes in 2015 was particularly significant in keeping his regime in control in Damascus.
The Times of London on Sunday reported that Mr. Tillerson would present Mr. Lavrov with evidence Russia knew about the gas attack and tried to cover it up. The Pentagon is investigating the possibility Russia bombed a Syrian hospital in a bid to destroy evidence of the attack, The Associated Press reported Friday.
But Mr. Tillerson was more circumspect Sunday, saying he had "not seen any hard evidence that connects the Russians directly to the planning or execution" of the attack, and that he hoped Moscow could be persuaded to rein in Mr. al-Assad.
The gassing of civilians, including children, in the town of Khan Sheikhoun last week appears to have changed Mr. Trump's mind on Syria. For several years before he became President, Mr. Trump argued there was little purpose in going after the regime in Damascus. But within two days of the gas attack, Mr. Trump ordered retaliation, launching 59 cruise missiles to pound the airfield from which he said Mr. al-Assad's forces had launched the attack.
Russia appeared taken aback by the swift action. At the UN Friday, Russian Deputy Ambassador Vladimir Safronkov described the U.S. air strike as a "flagrant violation of international law." On Sunday, the Russian embassy in London trolled Mr. Trump on Twitter, suggesting tensions would lead to a "war of clowns" and that people should be "appalled" at the prospect of Mr. Trump as a war leader.
In Syria, meanwhile, NGOs reported that warplanes had taken off from the bombed airfield the day after the missile strike.
Despite the heated rhetoric, the Trump administration contended Sunday it hopes to persuade Moscow to get Mr. al-Assad out of office as part of the ultimate resolution of Syria's civil war.
National-security adviser H.R. McMaster told Fox News it was "very difficult to understand how a political solution could result from the continuation of the Assad regime."
"We are not saying that we are the ones who are going to affect that change. What we are saying is, other countries have to ask themselves some hard questions. Russia should ask themselves, 'what are we doing here?' " he said.