Russia's government resigned on Wednesday after President Vladimir Putin proposed a shake-up of the constitution, in a shock announcement that fuelled speculation about Putin's future plans.
The resignation of Prime Minister Dmitry Medvedev -- a longtime Putin ally -- came after the president used his annual state of the nation address to propose a package of constitutional reforms that would strengthen parliament's role.
Speculation has swirled about changes to Russia's political system that would allow Putin to stay on after 2024, when he is due to step down after a fourth Kremlin term.
Some have suggested he could assume a new post or remain in a powerful behind-the-scenes role.
Putin on Wednesday proposed the little-known head of Russia's tax service Mikhail Mishustin for the post of prime minister, the Kremlin said in a statement.
The proposal to appoint 53-year-old Mishustin, a relatively obscure figure who has run the service since 2010, came after the surprise resignation of Dmitry Medvedev following Putin's proposal of a package of constitutional reforms.
The two met in the Kremlin where Putin "suggested to him that he take the post of the head of government" which he accepted, the Kremlin said.
Russia's lower house of parliament said it would decide on whether to approve Mikhail Mishustin, the head of the Federal Tax Service, as Russia's new prime minister on Thursday, the RIA news agency reported.
Medvedev and Putin appeared alongside each other on national television a few hours after Putin's address to say the government was stepping down.
Medvedev said the constitutional proposals would make significant changes to the country's balance of power and so "the government in its current form has resigned".
"All further decisions will be taken by the president," he added.
Putin thanked Medvedev -- who also served as Russian president for four years from 2008 -- and suggested that he take on a role as deputy head of Russia's Security Council, which Putin chairs.
'Demand For Change'
The changes Putin proposed on Wednesday would transfer more authority to parliament, including the power to choose the prime minister and senior cabinet members, instead of the president as under the current system.
Other changes would see the role of regional governors enhanced and residency requirements tightened for presidential candidates and other top officials.
"Today in our society there is a clear demand for change," Putin said in his address. "People want development, they are striving to move forward in their careers, in their education, in becoming prosperous."
The package of reforms would be put to a national vote, he said, without specifying when.
"We will be able to build a strong prosperous Russia only on the basis of respect for public opinion," the 67-year-old leader said.
Analysts said Putin was laying the groundwork for potential changes to a system in place since the early 1990s.
"Russia has entered its period of power transition ahead of schedule," said Tatiana Stanovaya, head of the R.Politik analysis firm.
She said it appeared Putin was preparing for a powerful post-presidential role as head of the State Council, an advisory body whose powers would be expanded under the constitutional reforms.
Medvedev had "become toxic", she said, and needed to make way for a new prime minister.
'Leader For Life'
Leading Kremlin critic Alexei Navalny said he expected any vote on constitutional changes to be "fraudulent crap" and that Putin's goal remained to be "sole leader for life".
Russia last conducted a referendum in 1993 when it adopted the constitution under Putin's predecessor Boris Yeltsin.
Putin has held a firm grip on the country since coming to power with Yeltsin's resignation in 1999, staying on as prime minister when Medvedev took the presidency.
Re-elected to a six-year term in 2018, Putin has seen his approval ratings fall to some of their lowest levels, though still far above those of most Western leaders.
Recent polls put Putin's rating at 68-70 percent, up a few points from a year ago but down from a high of more than 80 percent at the time of his last election.
Hit by Western sanctions over the 2014 annexation of Crimea, Russia's economy has stagnated and most Russians have seen their disposable income fall.
Frustration boiled over last summer, with thousands taking to the streets of Moscow to protest the exclusion of opposition candidates from local elections, leading to wide-scale arrests and long jail terms for a number of demonstrators.
The state of the nation address -- delivered in the Manezh exhibition hall next to the Kremlin -- is one of three big annual Putin events, along with a marathon press conference and live phone-in where he takes questions from the Russian public.