WASHINGTON — The Biden administration on Thursday announced the expulsion of 10 Russian diplomats and sanctions against dozens of people and companies as it moved to hold the Kremlin accountable for interference in last year's presidential election and the hacking of federal agencies.

The sanctions also target Moscow's ability to borrow money by prohibiting U.S. financial institutions from buying Russian bonds directly from Russian institutions.

The actions, foreshadowed for weeks by the administration, represent the first retaliatory measures announced against the Kremlin for the hack, familiarly known as the SolarWinds breach. In that intrusion, Russian hackers are believed to have infected widely used software with malicious code, enabling them to access the networks of at least nine agencies in what U.S. officials believe was an intelligence-gathering operation aimed at mining government secrets.

Besides that hack, U.S. officials last month alleged that Russian President Vladimir Putin authorized influence operations to help Donald Trump in his unsuccessful bid for reelection as president, though there's no evidence Russia or anyone else changed votes or manipulated the outcome.

Russia swiftly denounced the actions and warned of retaliation.

The measures announced Thursday include sanctions on six Russian companies that support the country's cyber activities, in addition to sanctions on 32 individuals and entities accused of attempting to interfere in last year's presidential election, including by spreading disinformation. The U.S. also sanctioned eight people and entities tied to Russia's occupation of Crimea.

The 10 diplomats being expelled include representatives of Russian intelligence services, the Biden administration said. 

Other measures are expected as well, though the administration is not likely to announce them. Officials have been advising that their response to Russia would be in ways both seen and unseen.

"These actions are intended to hold Russia to account for its reckless actions. We will act firmly in response to Russian actions that cause harm to us or our allies and partners," Secretary of State Antony Blinken said in a statement.

But, he added, "Where possible, the United States will also seek opportunities for cooperation with Russia, with the goal of building a more stable and predictable relationship consistent with U.S. interests."

The White House also said Biden was using diplomatic, military and intelligence channels to respond to reports that Russia encouraged the Taliban to attack U.S. and allied troops in Afghanistan based on the "best assessments" of the intelligence community. 

Reports of alleged "bounties" surfaced last year, with the Trump administration coming under fire for not raising the issue directly with Russia. The White House did not publicly confirm the reports. "The safety and well-being of U.S. military personnel, and that of our allies and partners, is an absolute priority of the United States," the White House said Thursday.

After the sanctions were announced, Russian Foreign Ministry spokeswoman Maria Zakharova warned that "such aggressive behavior will undoubtedly trigger a resolute retaliation."

"Washington should realize that it will have to pay a price for the degradation of the bilateral ties," Zakharova said, adding that "the responsibility for that will fully lie with the United States." 

She said the ministry has summoned the U.S. ambassador for a "hard conversation," but wouldn't immediately say what action Russia will take.

The sanctions send a clear retributive message to Russia and are aimed at serving as a deterrent. But they are certain to exacerbate an already tense relationship between the U.S. and Russia.

President Joe Biden told Putin this week in their second call to "de-escalate tensions" following a Russian military buildup on Ukraine's border, and said the U.S. would "act firmly in defense of its national interests" regarding Russian intrusions and election interference. 

In a television interview last month, Biden replied "I do" when asked if he thought Putin was a "killer." He said the days of the U.S. "rolling over" to Putin were done. Putin later recalled his ambassador to the U.S. and pointed at the U.S. history of slavery and slaughtering Native Americans and the atomic bombing of Japan in World War II.

It remained unclear whether the U.S. actions would actually result in changed behavior, especially since past measures by the U.S. have failed to bring an end to Russian hacking. The Obama administration expelled diplomats from the U.S. in 2016 in response to interference in that year's presidential election. And though Trump was often reluctant to criticize Putin, his administration also expelled diplomats in 2018 for Russia's alleged poisoning of an ex-intelligence officer in Britain.

U.S. officials are still grappling with the aftereffects of the SolarWinds intrusion, which affected agencies including the Treasury, Justice, Energy and Homeland Security departments, and are still assessing what information may have been stolen. The breach exposed vulnerabilities in the supply chain as well as weaknesses in the federal government's own cyber defenses.

The actions would represent the second major round of sanctions imposed by the Biden administration against Russia. Last month, the U.S. sanctioned seven mid-level and senior Russian officials, along with more than a dozen government entities, over a nearly fatal nerve-agent attack on opposition leader Alexei Navalny and his subsequent jailing.