Skripal, a former colonel in Russia's military intelligence service, and his 33-year-old daughter were found slumped unconscious on a bench in the southern English city of Salisbury in March after a liquid form of the Novichok type of nerve agent was applied to his home's front door.
Russia is already under USA sanctions for its 2014 invasion of Crimea, and the Trump administration expelled 60 Russians from the US and shuttered the Russian consulate in Seattle in response to the failed assassination attempt.
Since the March attack, two other British nationals with no ties to Russian Federation have been poised by the substance.
Russian authorities played down the importance of new USA sanctions, saying they have tools to maintain financial stability, after a new round of US penalties sent the rouble plunging to a two-year low.
The sanctions being used by the United States of America are economic - they ban companies from selling goods to Russian Federation.
The Trump administration has also already responded to the nerve agent poisonings. One of the victims, Dawn Sturgess, later died, leading police to launch a murder inquiry. "So linking these events is unacceptable to us, and just as with previous USA sanctions we believe are absolutely illegal and against worldwide law", Peskov told reporters.
The action follows the US Treasury's imposition of sanctions in March against 19 Russian citizens and five entities for interfering in the 2016 US election - the toughest steps against Moscow since President Donald Trump took office.
"I think that's the way we have to understand this.there's actually no logical reason for them to do this now", he said, noting that the United Kingdom hasn't produced any new evidence or information about the Skripal case which would have prompted the sanctions.
It's left the Russian rouble at a two year low and the Kremlin unhappy after last month's Helsinki summit between Trump and Putin suggested improving relations between the powers. This included siding with the Russian leader over US intelligence regarding alleged Kremlin interference in the 2016 elections that brought Trump to the White House.
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The US is trying to play up this "anti-Russian topic as a way to continue demonizing Russia" and make it appear that it is not fulfilling its global obligations, Zakharova said.
"Once again we deny in the strongest terms the accusations about the possible connection of the Russian state to what happened in Salisbury".
A former Defense Department official, Mark Simakovsky, said Wednesday that a second tranche would target Russian exports to the USA and theoretically could include restrictions on flights by the state airline Aeroflot as well as a downgrade of diplomatic relations.
Paul said the letter "emphasized the importance of further engagement in various areas including countering terrorism, enhancing legislative dialogue and resuming cultural exchanges".