Kazakhstan's interim president has ordered an early presidential election in two months' time.

Kassym-Jomart Tokayev, who became the acting head of state after last month's unexpected resignation of Nursultan Nazarbayev, said in Tuesday's televised address to the nation that the vote will be held on June 9.

Nazarbayev took the helm in Kazakhstan when it was still part of the Soviet Union and led it for three decades.

The 78-year-old has retained the honorary title of "Elbasy" or "Leader of the Nation" and is expected to continue to wield considerable political power as chairman of the nation's Security Council and the head of the ruling Nur Otan party.

Nazarbayev's eldest daughter has been named speaker of the upper chamber of parliament.