Russian President Vladimir Putin says he will become prime minister if his chosen successor, Dmitry Medvedev, wins the presidential election in March.
Russian prime ministers usually play second fiddle to the president
He was speaking at a conference in Moscow of the governing United Russia party, which has now confirmed Mr Medvedev as its candidate.
Mr Medvedev is expected to win, largely thanks to Mr Putin's own popularity.
Mr Putin is legally barred from serving a third consecutive term as president but could stand again in 2012.
"If the citizens of Russia trust Dmitry Medvedev and elect him the country's president I will be ready to chair the government," he told the United Russia conference.
Mr Putin's announcement ended speculation he might seek another route to remain at the heart of Russian government.
When United Russia effectively turned this month's parliamentary election into a referendum on his presidency, the party's resulting landslide was portrayed as a message from Russian citizens that Mr Putin should retain some national leadership role.
"I don't have the slightest doubt that [Mr] Putin... will keep using his enormous political and professional resources, his influence both in our society and in the world, for the benefit of Russia and its citizens," Mr Medvedev said.
For his part, Mr Putin told the conference he was not afraid "of transferring... the destiny of Russia to the hands of [Dmitry Medvedev]".
Reacting to news of the Putin-Medvedev tandem, the White House said it was an internal Russian affair if Mr Putin became prime minister after the next election.
"We believe that we'll be able to have good relations with Russia moving forward," said spokeswoman Dana Perino.
Mr Medvedev has already pledged to adhere as a leader to the policies outlined during the Putin presidency.
He said last Tuesday that he wanted the benefits of economic growth to reach all sections of Russian society.
The 42-year-old former lawyer managed Mr Putin's election campaign in 2000 and is now chairman of state energy giant, Gazprom.
As first deputy prime minister, he has also overseen national programmes in the areas of health, housing and education.
Russia has made huge economic gains as a result of soaring international oil prices.
The government has been facing demands to channel energy revenues into pensions, benefits and parts of the country's infrastructure that have been decaying since the collapse of the Soviet Union.