"Today, the Department informed Congress we could not certify that the Russian Federation met the conditions required by the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991," Nauert said. "We intend to proceed in accordance with the terms of the CBW Act, which directs the implementation of additional sanctions."
The United States has accused Russia of involvement in the March 4 nerve agent attack on Skripal and his daughter Yulia in the English town of Salisbury, a claim repeatedly denied by Moscow.
"The Chemical Biological Weapons Act mandates that the State Department certify to the Congress whether Russia has met conditions required by the law three months after the initial determination of the Skripal case. That initial determination was made August 6, and that takes us to November 6," State Department Deputy Spokesperson Robert Palladino said in a press briefing last week.
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The conditions imposed by Washington on Moscow include Russia ceasing its alleged chemical weapons and assuring it will not use them, as well as allowing international inspectors to verify those assurances, according to the State Department.
Palladino also said there is no timeline associated with the State Department’s consultations with Congress on the new wave of sanctions against Russia.
On August 24, the United States announced that it was imposing sanctions on Russia under the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991. The law allows for the termination of foreign assistance and arms sales, denial of US government credit or other financial assistance, prohibitions on exports and a suspension of diplomatic relations, among other possible measures.