Dmitry Medvedev has vowed to continue the course of predecessor Vladimir Putin after winning a landslide victory in Russia's presidential election.
Mr Putin (left) congratulated Mr Medvedev late on Sunday
With nearly 100% of the ballots counted, the election commission has announced he won 70.23% of the vote.
Mr Medvedev said he hoped to work in an "effective tandem" with Mr Putin as his prime minister.
As president, he said, he would control foreign policy with the defence of Russian interests his chief priority.
Mr Putin, he confirmed, would be moving out of the Kremlin.
Mr Medvedev's nearest rival was Communist leader Gennady Zyuganov, with 17.76% of the vote. He vowed to go to court over alleged fraud, Itar-Tass news agency reports.
The mainly pro-Kremlin media have welcomed a Medvedev victory.
The Izvestia newspaper said the vote was a "triumph of the majority" that created a "bridge to the future for Russia".
Mr Putin late on Sunday congratulated Mr Medvedev on his big lead when they appeared together at a rally in Moscow's Red Square.
Speaking to reporters later, Mr Medvedev said his policies would be "a direct continuation of that path which is being carried out by President Putin".
Asked about foreign policy, he said "the president defines Russia's foreign policy according to the constitution".
Russia's priorities would, he said, continue to be its fellow ex-Soviet republics.
On where Mr Putin would work as prime minister, he said "the place of the prime minister and the government is the White House", referring to the government building a few miles from the Kremlin.
A first deputy PM, Mr Medvedev was the clear favourite from the start and enjoyed generous television coverage.
Mr Putin, who has been in office for eight years, was barred by the constitution from seeking a third term, but has pledged to serve as Mr Medvedev's prime minister.
Turnout was high, at 69.65%, officials said. But there were reports that many workers were told by their bosses to vote.
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Various inducements were also offered to mobilise voters, including cheap food, free cinema tickets or toys, correspondents say.
After polls closed Mr Zyuganov said there had been widespread irregularities.
"We will go to court over this," Itar-Tass quoted him as saying.
The Kremlin has dismissed claims of fraud.
There has been very little scrutiny of voting by Western election observers, many of whom stayed away.
The main independent Russian observer group, Golos, said the turnout was impossibly high in some regions.