The US is poised to impose significant sanctions on Russia following the death of opposition leader Alexei Navalny and the continuing conflict in Ukraine.

Alexei Navalny's family is requesting the return of his remains, while his widow accuses Russian President Vladimir Putin of orchestrating Navalny's death.

Preparations for major US sanctions are underway, coinciding with reports of a dual national's arrest in Russia on charges of state treason.

The Kremlin has rejected calls for an international probe into Navalny's death, dismissing claims of any concealment.

In the face of adversity, Yulia Navalnaya pledges to uphold the mission of her late husband, Alexei Navalny.