Russia's government has resigned, hours after President Vladimir Putin proposed sweeping constitutional changes that could prolong his stay in power.

Prime Minister Dmitry Medvedev said the president's proposals would significantly change Russia's balance of power.

Putin asked  Medvedev to become deputy head of the National Security Council, which is chaired by Putin.

The president later nominated tax service chief Mikhail Mishustin to replace Medvedev as prime minister.

The unexpected announcement comes four years before Putin's fourth term of office is due to end.

Under the existing constitution, he would not be entitled to another term.

The Russian leader said during a speech to both chambers of parliament that there would be a nationwide vote on changes that would shift power from the presidency to parliament.

[Source:BBC]