US President Joe Biden on Thursday met with the wife and daughter of Russian opposition leader Alexei Navalny, who died last week, “to express his deepest condolences,” the White House said, according to Reuters.

During the meeting in California, Biden expressed his admiration for Navalny’s “extraordinary courage and his legacy in the fight against corruption and for a free and democratic Russia where the rule of law applies equally to all,” the White House said in a statement.

Biden also said the United States would announce major new sanctions against Russia on Friday in response to Navalny’s death, Russia’s repression and aggression and its war in Ukraine, he added.

White House national security adviser Jake Sullivan previously said the latest punitive measures would target the country’s industrial and defense bases, as well as sources of revenue for the economy.

Navalny, 47, lost consciousness and died suddenly on Friday after a walk in the Polar Wolf colony, the penitentiary service said.

Oleksiy Navalny’s mother Lyudmila reported on Thursday that she was secretly taken to the Salekhard morgue, where she was shown her son’s body. She accuses Russian investigators of plans to bury her son in secret, without a funeral, and of “blackmail” and “threats” against her, Reuters reports. At the same time, the team of Oleksiy Navalny’s opponent stated that the politician’s death certificate stated that he died of natural causes.