The funeral of Russian opposition leader Alexei Navalny, who died earlier this month in a remote Arctic penal colony, will take place on Friday at Moscow after several locations declined to host the service, his spokeswoman said.

His funeral will be held at a church at Moscow’s southeast Maryino district on Friday afternoon, Kira Yarmysh said Wednesday. The burial is to be at a nearby cemetery.

Navalny died in mid-February in one of Russia’s harshest penal facilities. Russian authorities said the cause of his death at age 47 is still unknown, and the results of any investigation are likely to be questioned abroad. Many Western leaders have already said they hold President Putin responsible for his death.

Ms. Yarmysh spoke of the difficulties his team encountered in trying to find a site for a “farewell event” for Navalny.

Most venues said they were fully booked, she tweeted, with some “refusing when we mention the surname ‘Navalny,’” and one disclosing that “funeral agencies were forbidden to work with us.”

The director of Navalny’s Anti-Corruption Foundation, Ivan Zhdanov, said the funeral was initially planned for Thursday — the day of Mr. Putin’s annual address to Russia’s Federal Assembly — but no venue would agree to hold it then.

“The real reason is clear. The Kremlin understands that nobody will need Putin and his message on the day we say farewell to Alexei,” Mr. Zhdanov wrote on Telegram.