Mr Kadyrov controls a powerful militia accused of rights abuses

The move followed days of speculation that Mr Alkhanov could resign amid a power struggle with his prime minister.

Mr Kadyrov, 30, is the son of the pro-Moscow ex-president Akhmad Kadyrov, who was assassinated in 2004.

He controls a militia accused by rights group of a role in murder and abduction of suspected separatist rebels.

The BBC's Artyom Liss in Moscow says that there has always been bitter rivalry between him and Mr Alkhanov - who never held much real power - and in the past few months the president's resignation only seemed a matter of time.

Mr Kadyrov will still need the approval of the local parliament, our correspondent adds, but his enormous popularity in the volatile southern republic means it will probably be just a formality.