The United States (US) has expelled 35 Russian diplomats as punishment for alleged interference into the presidential election last month.
It will also close two Russian compounds used for intelligence-gathering, in Maryland and New York, as part of a raft of retaliatory measures.
President Barack Obama had vowed action against Russia amid US accusations it directed hacks against the Democratic party and Hillary Clinton’s campaign.
Russia has denied any involvement.
On Wednesday, senior US senators called for increased sanctions.
But President –elect Donald Trump, who has been criticised for being too cosy with Russia, told reporters outside his Florida resort the issue of retaliation was a distraction and there was no conclusive evidence who was behind the hacks.
“I think we ought to get on with our lives,” he said.
“I think that computers have complicated lives very greatly. The whole age of the computer has made it where nobody knows exactly what’s going on.
“We have speed, we have a lot of other things, but I’m not sure we have the kind of security we need.”
The US intelligence agencies are in agreement that hackers linked to the Kremlin accessed emails belonging to the Democratic National Committee and the emails of a top Hillary Clinton aide.
Contents from the emails were made public, in an embarrassing series of stories for Mrs Clinton throughout the final stages of her campaign.
Republican Senator Lindsey Graham has called for new measures aimed at Russian leader Vladimir Putin “as an individual”.
Asked about that, Trump referred to Graham’s failed presidential bid.
“I don’t know what he’s doing,” said the president-elect. “I haven’t spoken to him. As you know, he ran against me.”
