Vladimir Putin has started a sweeping revamp of Russia’s leadership, replacing his long-serving prime minister with a little-known technocrat and launching a constitutional overhaul that could allow him to wield power after the end of his presidential term in 2024.

Russia’s leader used his annual state of the nation address to propose a referendum to endorse big changes to the country’s political system, including plans to curb the powers of the future president and boost those of parliament. The reforms to the way Russia is governed could pave the way for Mr Putin to extend his 20-year rule in a new capacity.

Shortly after Mr Putin announced the plans, Dmitry Medvedev, the premier, said he would stand down along with the rest of the cabinet. Mr Putin then chose Mikhail Mishustin, head of Russia’s tax service, to become the next prime minister — an appointment parliament will pass on Thursday.