Lyudmila Navalnaya says investigators are trying to set conditions on where, when and how the prominent Kremlin critic should be buried.

The mother of Alexey Navalny has said Russian authorities are pressing her to bury the opposition leader’s body in “secret”.

Speaking in a video message posted on YouTube on Thursday, Lyudmila Navalnaya said Russian authorities had allowed her to see her son’s body in the morgue.

She said investigators were “blackmailing” her over the funeral of the Kremlin critic, who died in detention last week, and trying to force her to hold a private burial ceremony without mourners.

“They want this to be done secretly, with no farewell. They want to bring me to the edge of a cemetery, to a fresh grave and say: ‘Here lies your son.’ I don’t agree to this,” she said.

There was no immediate comment from Russian authorities.

Navalnaya said she had been taken to the morgue and shown Navalny’s body on Wednesday evening. On Tuesday, she made an appeal to Russian President Vladimir Putin. “Let me finally see my son,” she said, urging authorities to release his body so she could bury him.

Navalny’s team said the death certificate, also seen by Navalnaya on Wednesday, stated that he had died of natural causes.

Navalny, Russia’s best-known opposition politician, died suddenly in an Arctic penal colony last Friday at the age of 47. His aides and family have alleged that the Kremlin murdered him, an allegation Russia has rejected.

“The investigators claim that they know the cause of death,” said Navalnaya, dressed in black and speaking in a calm voice on video. “They have all the medical and legal documents ready, which I saw, and I signed the medical death certificate.

“According to the law, they should have given me Alexey’s body right away, but they have not done so until now. Instead, they are blackmailing me, setting me conditions on where, when and how Alexey should be buried. This is illegal.”

Navalny’s mother said: “I’m recording this video because they started threatening me. Looking into my eyes, they say that if I don’t agree to a secret funeral, they will do something with my son’s body.”

She quoted one of the investigators as saying: “Time is not on your side; corpses decompose.”

“I don’t want special conditions,” she said.

“I just want everything to be done according to the law. I demand that my son’s body be returned to me immediately.”

‘We can handle anything’

Earlier on Thursday, Navalny’s widow Yulia published a picture of her mourning with the couple’s grieving daughter Dasha.

“My sweet little girl. I flew to you to hug and support you, but you are sitting there supporting me,” Yulia Navalnaya wrote in a post published on Instagram.

“You are so strong, so brave and steadfast. We can handle anything, my heart. How good that you are by my side.”

Navalny has a 15-year-old son as well as 23-year-old Dasha, who studies in the United States. Dasha had repeatedly made demands for the release of her imprisoned father and had also given speeches in his honour at award ceremonies.

Navalny’s widow did not immediately travel to see her children when his death was announced on Friday, but instead visited the Munich Security Conference, where she blamed Russian President Vladimir Putin for her husband’s fate.

The Kremlin has said it had nothing to do with Navalny’s death, and that the circumstances are being investigated. Putin has yet to comment on it.