U.S. officials are expressing "high confidence" that Syria carried out last week's chemical weapons attack in the town of Douma, promising the West will respond and that all options remain on the table.
Despite Tweets from U.S. President Donald Trump earlier this week suggesting a missile strike might be imminent, the White House, State Department, and Pentagon have been cautious in their language, emphasizing the need to forge an airtight case against the government of Syrian President Bashar al Assad.
By late Friday, there were indications such a case was coming together.
"We have a very high confidence that Syria was responsible," White House Press Secretary Sarah Sanders told reporters at a briefing.
"We also hold Russia responsible for their failure to stop chemical weapons attacks from taking place," Sanders added. "Russia's failure to stop them and their continued [inaction] on this front has been part of the problem."
The State Department went one step further, claiming the U.S. now has definitive proof.
"We can say that the Syrian government was behind this attack," said spokeswoman Heather Nauert.
"We know that this was a chemical weapon that was used in Syria," Nauert said. "The kind or the mix, that we are still looking into."
Despite such confidence, other U.S. officials remained wary, warning while Syria's use of chemical weapons cannot be tolerated, much more is at stake given the backing it gets from Moscow.
"This is a chess game and the Russians are ratcheting up the pressure," a U.S. official told VOA on the condition of anonymity given the sensitivity of the situation. "They're playing dirty," the official added. "We need to think two or three steps ahead."
Russia, long an ally of Syrian President Bashar al-Assad, has warned a military conflict could erupt if the U.S. and its Western allies take action in Syria.
"We hope that ... the U.S. and their allies will refrain from military action against a sovereign state," Russian Ambassador to the U.N. Vassily Nebenzia said Friday.
Also Friday, Moscow alleged it had "proof that testifies to the direct participation of Britain" in staging the chemical attack in Douma.
Britain pressured the White Helmets, volunteers and activists who serve as first responders in rebel-held areas, to stage the attack, Defense Ministry spokesman Igor Konashenkov said.
Britain called the allegation a "blatant lie."
美国官员表示“高度确信”叙利亚发动了上星期东古塔杜马镇的化学武器袭击案，并且表示西方会做出反应，而且各种选项都不排除。
虽然美国总统川普本星期早些时候发推表示可能立刻进行导弹打击，但是白宫、国务院和五角大楼用词都一直比较谨慎，强调需要找齐针对叙利亚总统阿萨德政府的铁证。
到了星期五傍晚，有迹象显示这样的证据正在汇集起来。
白宫发言人桑德斯在记者会上说，“我们非常确信这是叙利亚干的。”
桑德斯还说，“我们认为俄罗斯也有责任，因为他们未能阻止化武攻击的发生。俄罗斯未能阻止而且继续无动于衷，这是问题的部分所在。”
美国国务院更是迈进了一步，宣称美国掌握了确凿证据。
国务院女发言人诺尔特说：“我们可以说，叙利亚政府指使发动了这次袭击。”
她说：“我们知道在叙利亚使用了化学武器，我们正在研究这种化学制剂。”
虽然这些官员十分确信，但是另一些美国官员很小心。他们提醒说，虽然叙利亚使用化学武器是不可容忍的行为，但是鉴于叙利亚得到俄罗斯的支持，此事有更大的危险。
一名官员以不透露姓名为条件对美国之音说，“这是一场棋赛，俄罗斯人加大了压力。他们耍赖。我们每走一步需要多想几步棋。“
俄罗斯呼吁叙利亚牵涉到的各方避免采取可能导致这个地区局势不稳的行动。
俄罗斯常驻联合国代表瓦西里·涅边贾大使说：”我们希望美国及其盟国实行克制，不要对一个主权国家采取军事行动。”
俄罗斯星期五还指责英国策划伪造了化武袭击的现场。
俄罗斯国防部发言人伊戈尔·科纳申科夫说，英国向“白盔队”民防组织施加压力，迫使他们伪造袭击的画面。“白盔队”由志愿人员和活动人士组成，他们是反政府力量控制区率先对应急事态做出反应的人员。
英国则驳斥说，这是“赤裸裸的谎言”。