The top Democrat on the House Intelligence Committee said Russia is absolutely "complicit" in the chemical attack in Syria that killed at least 86 civilians, including many children.
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"Absolutely they're complicit," Rep. Adam Schiff of California told ABC News Chief Anchor George Stephanopoulos on "This Week" Sunday. "Russian intelligence may not be as good as ours, but it's good enough to know the Syrians had chemical weapons, were using chemical weapons."
Schiff added that Russia is "better positioned to know, in the sense that they have people on the ground in close proximity working in close concert with the regime. I think absolutely they know what the Syrians are doing."
The U.S. blames Syria's government for the deadly chemical attack on a rebel-held province last week. The Assad government has denied responsibility, and Russia has said that the release of toxic agents happened when a Syrian airstrike hit a rebel chemical-weapons arsenal and munitions factory.
The question of Russian complicity in the attack also came up in an earlier interview on "This Week" Sunday with Secretary of State Rex Tillerson.
Tillerson said he has "not seen any hard evidence" that Russians were involved in planning or carrying out the attack.
But the secretary of state said when he meets with the Russian foreign minister this week, he will bring up Russia's obligation under a 2013 agreement to ensure the Syrian government got rid of its chemical weapons.
"It agreed to be the guarantor of the elimination of the chemical weapons, and why Russia has not been able to achieve that is unclear to me," Tillerson said. "Clearly they've been incompetent and perhaps they've just simply been out-maneuvered by the Syrians."
Within less than three days after the chemical attack in Syria, President Trump ordered a U.S. missile strike on the Syrian air base where the aircraft which carried the chemical weapons are believed to have flown from.
Rep. Schiff told Stephanopoulos, "I think there's a strong moral case ... to make for what the president did" in response to the chemical attack.
"But I don’t think, George, it should have been done without congressional approval," the lawmaker added.
"Do you think Congress could even come close to agreeing on a use of force resolution at this point?" Stephanopoulos asked, referring to the sharp partisan divide.
"You know, I do," the Democratic lawmaker replied. "It's certainly not easy ... [But] I think we can come to agreement on a resolution that says the president will have the authority to go after al-Qaeda and ISIS and the Taliban."
Such a resolution "forces accountability," Schiff said.