The sanctions are mandated under the Chemical and Biological Weapons and Warfare Elimination Act of 1991, which says the USA president shall tighten the penalties within 90 days unless Moscow provides "reliable assurances" that it no longer engages in such activities, and allows on-site inspections by United Nations observers.
The new sanctions were to take effect following a 15-day Congressional notification period, she said.
Moscow still denies any involvement in the March 4 attack in Salisbury, England, and calls the United States response "categorically unacceptable".
The State Department's announcement fuelled already worsening investor sentiment about the possible impact of more sanctions on Russian assets and the rouble at one point slid by over one per cent against the dollar, hitting a two-year low, before recouping some of its losses.
"The United States needs to finally understand that it's useless to fight with Russian Federation, including with the help of sanctions", he said.
A senior Russian lawmaker denounced the sanctions as "lynch law". -Russian relations. A 1991 law, however, mandates sanctions once the president makes a determination that a country is responsible for a chemical or biological weapons attack.
Camera IconUS President Donald Trump left and Russian President Vladimir Putin right shake hands in Helsinki
Peskov highlighted on Thursday what he called the "unpredictability of Russia's partners across the Atlantic.you can expect anything from Washington", he told CBS News partner network BBC News, calling the us, "an unpredictable worldwide player".
The sanctions came as an eagerly-watched contest for a previously safe Republican seat in the U.S. congress went to the wire, leading to speculation that voters were turning against Donald Trump and could punish the Republican Party at mid-term elections.
Trump made no public comments on the matter, and communications aides referred all questions to the State Department, which said the US still sought improved ties with Moscow. (Authorities believe a British woman's death was caused by accidental exposure to the nerve agent).
"The UK welcomes this further action by our U.S. allies", a No 10 spokesman said.
The head of the foreign-relations committee of Russia's Senate, Konstantin Kosachev, compared the new sanctions to a "lynching".
The Kremlin said the new sanctions were "illegal and do not correspond to worldwide law".
"This whole accusatory pyramid is being built in the absence of any legal substantiation, but they're still telling us about worldwide law and respect for legal obligations", Zakharova told the Moscow briefing.
He added that the United States move was "absolutely unfriendly", but reiterated Moscow's hope for improvements to the stressed relations between the two countries.