The US has imposed sanctions on 19 Russians, accusing them of interference in the 2016 US election and alleged cyber-attacks.
They include 13 individuals charged last month by Justice Department Special Counsel Robert Mueller.
Treasury Secretary Steven Mnuchin accused the Russians of “destructive cyber-attacks, and intrusions targeting critical infrastructure”.
He said the sanctions would target “ongoing nefarious attacks” by Russia.
Five groups including Moscow’s intelligence services are targeted in Thursday’s measures.
The sanctions are being described in Washington as the strongest action taken by the Trump administration thus far against Moscow.
The US treasury secretary said there would be additional sanctions to hold Russian “officials and oligarchs accountable for their destabilising activities”.
He did not specify when these penalties would be imposed, but stated they would sever the individuals’ access to the US financial system.
Russian Deputy Foreign Minister Sergei Ryabkov said Moscow was calm about the new sanctions, according to Interfax news agency.
Mr Ryabkov said Moscow had already begun drawing up retaliatory measures.
At the White House, where he is hosting Irish Prime Minister Leo Varadkar, Mr Trump agreed with British allegations that the Kremlin was behind the poisoning of a former spy in southern England.
The UK has blamed Russia for the attack and is expelling 23 of its diplomats, but Moscow denies all involvement.
“It certainly looks like the Russians were behind it,” said Mr Trump, “and we’re taking it very seriously.”
Source: BBC
