Saturday alleged President Vladimir Putin of torturing his corpse and accused him as "demonic".
In a video posted on YouTube, Navalnaya demanded Russian authorities to release Navalny's body for burial and questioned Putin's often-professed Christain faith.
Navalny's mother, Lyudmila Navalnaya had said earlier that Russian investigators were refusing to release his body from the morgue until she agrees to lay him to rest without a public funeral.
Meanwhile, Navlany's aides had said that the authorities had threatened to bury him in the remote prison colony where he died unless his family agreed to their conditions.
"We already knew that Putin’s faith was fake, but now we see it more clearly than ever before," said Navalnaya in the video.
“No true Christian could ever do what Putin is now doing with Alexei’s body," she added.
“Give us back the body of my husband. We want to hold a funeral service and bury him in a humane way, in the ground, as is customary in Orthodox Christianity," said Navalnaya.
However, Kremlin spokesman Dmitry Peskov rejected allegations that Putin was involved in Navalny's death, calling them absolutely unfounded, insolent accusations about the head of the Russian state.
Navalny's spokesman, Kira Yarmysh, said on X, formerly Twitter, that Lyudmila Navalnaya was shown a medical certificate stating that her son died of natural causes.