Russian opposition leader Alexei Navalny's associates allege he was close to being freed in a prisoner swap involving the US and Germany before his death.

Maria Pevchikh, a top aide to Navalny, claims that a deal was nearly reached, offering a convicted assassin in Germany for Navalny and two Americans.

The circumstances of Navalny's death are under scrutiny, with his family only receiving his body after a week of disputes with Russian authorities.

Western nations have implemented additional sanctions against Russia, linked to both Navalny's death and the ongoing conflict in Ukraine.

Plans are being made for a memorial service for Navalny, while Russian President Vladimir Putin has not made any public statements regarding the incident.