A priest who oversaw a memorial for late Russian opposition leader Alexei Navalny has been suspended for three years by the head of the country's Orthodox Church.

Dmitry Safronov held a memorial service by Navalny's grave in Moscow on March 26 to mark 40 days since the politician's death, an important ritual within Russian Orthodox tradition.

An order published Tuesday on the Moscow diocese website publicly demoted Safronov from his position as priest to that of a psalm-reader and stripped him of the right to give blessings or to wear a cassock for the next three years. He was also transferred to another church within the capital.

No reason was given for the decision, which was signed by Patriarch Kirill, the head of the Russian Orthodox Church and a key ally of Russian President Vladimir Putin.

Navalny died suddenly on Feb 16 in the remote Arctic penal colony where he had been serving a 19-year sentence on extremism charges widely seen as politically motivated. The cause of Navalny's death remains unexplained, although the politician's allies have blamed the Kremlin for his demise.

Russian authorities initially refused to release Navalny's body, citing the need for further investigations. The politician's team later said that they had struggled to find a hearse to transport Navalny's body after funeral directors had received threats from unknown individuals.

Safronov was among the clergymen who previously signed a public letter calling for Navalny's remains to be returned to his family.

During his more than two decades in power, Putin has massively boosted the Russian Orthodox Church's standing, increasing its prestige, wealth and power after decades of oppression or indifference under Soviet leaders.

In turn, its leaders, like Patriarch Kirill, have supported his initiatives. The church has thrown its weight behind the war in Ukraine and it has been commonplace to see its clergymen blessing troops and equipment heading into battle and invoking God's blessings in the campaign.