President Donald Trump’s administration has accused Russia of trying to shield Syria’s government from blame for a deadly gas attack.
Mr. Trump, who has faced criticism for lacking a broader strategy to deal with the Syria crisis, insisted he has no plans to “go into” the war-torn country.
Senior White House officials, briefing reporters on condition of anonymity, said Mr. Assad’s government carried out the April 4 sarin nerve gas attack on civilians in Syria’s Idlib province.
At least 87 people, including many children were killed in the attack.
Russia has defended the Syrian leader against U.S. allegations that his forces carried out the attack, saying there was no evidence.
Russia has blamed Syrian rebels.
“It’s clear that the Russians are trying to cover up what happened there,” one White House official said.
White House spokesman Sean Spicer later told reporters that the facts backed up the U.S. version of events.
“Russia is on an island when it comes to its support of Syria or its lack of, frankly, acknowledgment of what happened,” he told reporters.
However, at the same briefing, Spicer drew criticism after he sought to underscore the ghastliness of the gas attack by saying: “You had someone as despicable as Hitler who didn’t even sink to using chemical weapons.
“Nazi Germany used gas chambers to kill millions of Jews during the Holocaust.
Spicer later apologised and said he should not have made the comparison.
The White House officials said Russia has frequently offered multiple, conflicting accounts of Syrian government aggression including the incident in the village of Khan Sheikhoun to sow doubt within the international community.
The U.S. launched 59 cruise missiles at a Syrian airfield on Thursday to retaliate after the attack.
The strikes thrust Trump, who came to power in January calling for warmer ties with Russia, and his administration into confrontation with Moscow.
Chinese President Xi Jinping told Mr. Trump in a telephone call on Wednesday that “any use of chemical weapons is unacceptable” and urged a political solution for Syria, Chinese state broadcaster CCTV said of the telephone exchange.
“(We) must persevere with moving towards a political solution for the Syria issue. It is very important that the United Nations Security Council maintains unity on the Syria issue.
“(I) hope the Security Council can speak with a single voice,” CCTV cited Xi as saying.
Trump’s ambassador to the United Nations, Nikki Haley, said on Tuesday she thought Russia knew about the chemical attack in advance.
“They didn’t look shocked. They didn’t look surprised. They were so quick to defend. And then the evidence comes out, and we see exactly what it is and we know exactly what the environment was. Then you realise,” she said on CNN.
U.S. intelligence indicates that the chemical agent in the attack was delivered by Syrian Su-22 aircraft that took off from the Shayrat airfield, according to a White House report given to reporters.
In a four-page document, the White House sought to rebut many of Moscow’s claims about the circumstances of the attack.
It said the Syrian planes were in the vicinity of Khan Sheikhoun about 20 minutes before the attack and left shortly afterward.
“Additionally, our information indicates personnel historically associated with Syria’s chemical weapons program were at Shayrat airfield in late March making preparations for an upcoming attack in northern Syria, and they were present at the airfield on the day of the attack,” the report said.
Washington wants Russia to stop supporting Assad, who has been fighting a six-year-long civil war against mostly Sunni Muslim rebels, also with the backing of Shi’ite Muslim Iran.