Russian opposition leader Alexei Navalny's body was given to his mother after Russian officials gave Navalny's mom a three-hour ultimatum to accept a secret burial or prison burial, Navalny's spokesperson said Saturday.

The big picture: President Biden has said Navalny's prison death on Feb. 16 is the impetus for new sanctions aimed at both Russian officials and its war machine in play in Russia's invasion of Ukraine.

Driving the news: Medical documents Navalny's mother, Lyudmila Navalnaya, signed required authorities to release his body two days after learning the cause of death, Navalny's spokesperson Kira Yarmysh said on X.

• Those two days expired on Saturday while Navalnaya was in the Russian town Salekhard.
• "The funeral is yet to come," Yarmysh said in a translation of the X post.
• "We don't know whether the authorities will interfere with carrying them out the way the family wants and as Alexei deserves."

Between the lines: Biden has said he believes Russian President Vladimir Putin is behind Navalny's death.

• Navalny's allies and family have said they believe high-level Russian authorities were involved in his death, given his status as Putin's foremost critic and the Kremlin-linked assassination attempt Navalny previously survived.

Flashback: Boris Nemtsov, a liberal politician and the most vocal critic of Putin when he was assassinated near the Kremlin in 2015, was given a public burial in Moscow, which drew thousands of mourners.

What's next: Biden has met with Navalny's wife, Yulia, and daughter, Dasha, the president said in an X post Saturday.

• "We're not letting up," he said about preserving Navalny's legacy. "His vision for a brighter future for Russia will live on."

Go deeper: U.S. imposes new sanctions on Russia over Navalny's death