The US has announced a range of new sanctions against Russia in response to what it says are cyber-attacks.
The measures, detailed in an executive order signed by President Joe Biden, are aimed at deterring “Russia’s harmful foreign activities”, the White House said on Thursday.
The moves target 32 Russian entities and include the expulsion of diplomats.
The US accuses Russia of malicious cyber-activity and interference in the 2020 presidential elections.
The executive order also bars US financial institutions from purchasing rouble-denominated bonds from June.
The measures come at a tense time for US-Russia relations.
They are the second major round of sanctions against Moscow after seven mid-level and senior Russian officials, and more than a dozen government entities, were targeted over the poisoning of Kremlin critic Alexei Navalny last month. Russia says it had no part in the poisoning.
In a call with Russian President Vladimir Putin on Tuesday, Mr Biden said the US would “act firmly” in defence of its national interests.
Mr Biden also proposed a meeting with Mr Putin “in a third country” that could allow the leaders to find areas to work together.
But Kremlin spokesman Dmitry Peskov said any new sanctions, which he described as illegal, would not help plans for a summit.
What’s behind this latest move?
Last year, cyber-security researchers identified a hack in a piece of software called SolarWinds – an intrusion that gave cyber-criminals access to 18,000 government and private computer networks.
Intelligence officials believe Russia was behind the attack. The hackers gained access to digital files of several US government agencies, including the treasury, justice and state departments.
Microsoft president Brad Smith said in February the SolarWinds hack was “the largest and most sophisticated” the world had ever seen.
Last December then US Secretary of State Mike Pompeo said he believed Russia was behind the attack but US investigators “were still unpacking precisely what it is”.
The US is now set to formally accuse Russian intelligence of carrying out the hack. Russia has denied any involvement.
Signalling a tougher line
The revelations of a major Russian cyber-campaign called Solar Winds last year caused dismay in Washington and raised difficult questions about how to respond.
Some in Congress likened it to an “act of war” and demanded retaliation. But others pointed out that the Russians had simply been engaged in exactly the kind of espionage that America itself also carries out online.
In the end, the Biden administration came to a view that the scale of the compromise of US systems required some response – but the question was what. Some of the response will be carried out “covertly” – probably using offensive cyber techniques to degrade the systems of those involved in Russia.
But there was also a debate about how far to link the cyber-incidents to other Russian intelligence activity the US was unhappy about, including interference in the 2020 election, offering bounties to the Taliban for attacks on US soldiers in Afghanistan, and activities in Ukraine. Some favoured keeping issues separate.
In the end, it appears the Biden team have opted to lump all of these issues together with one major response to try to maximise the impact.
But will this actually deter Russia? Past experience suggests it is unlikely.
Moscow has for some years believed it is engaged in a conflict with the West, although at a threshold below that of traditional war, and the US retaliation will just confirm that.
What it will do, though, is signal inside the US and around the world that the Biden administration is going to take a tougher line than that of Donald Trump.
Why are things so bad between Russia and the US?
In his first foreign policy speech in February, Mr Biden made it clear he planned to stand up to Russia, pledging to hold it to account for alleged cyber-attacks and election interference.
“The days of the United States rolling over in the face of Russia’s aggressive actions… are over,” he said.
The quote provided a stark contrast to the words of his predecessor, Donald Trump, who rarely criticised Mr Putin.
In a report last month, US intelligence agencies concluded the Russian president had probably directed online efforts to help Donald Trump win a second term as US president.
The US has also publicly warned Russia against aggressive actions in Ukraine. Russia is beefing up its military presence near Ukraine’s’ eastern border.
And in a televised interview last month, when asked if he thought Mr Putin was a “killer”, the US president replied “I do”.
What has Russia said?
Mr Peskov on Wednesday said that sanctions would “in no way” the prospect of a summit.
According to reports, the US ambassador in Moscow was told by Russian officials that Washington must refrain from new sanctions if it wanted to mend the relationship.
Mr Peskov also appeared to explain troop movements near Ukraine as a way of anticipating US actions such as sanctions.
“The hostility and unpredictability of America’s actions force us in general to be prepared for the worst scenarios,” he said last week.