| SKOLKOVO, Russia
SKOLKOVO, Russia President Dmitry Medvedev spelled out differences with Prime Minister Vladimir Putin on Wednesday over modernization of the economy and the fate of a jailed oil tycoon, but kept Russia guessing which of them will run in the 2012 presidential election.
Medvedev and Putin, who steered him into the Kremlin in 2008, have suggested one of them will run for a six-year term as president next March, but with less than a year remaining they have yet to say who it will be.
In a more than two-hour news conference broadcast live to the nation, a confident and relaxed-looking Medvedev underlined his credentials as a strong and independent leader but refused to be drawn on the 2012 election.
"To announce such a decision, formats different from a press conference should be chosen," Medvedev told more than 800 journalists at the biggest news conference of his presidency in Skolkovo, an area near Moscow that is to become a high-tech hub.
The Kremlin leader, who joked with reporters and carried a tablet computer to the stage with him, promised a decision would be announced soon.
Medvedev, 45, has presented himself as an alternative to the 58-year-old Putin, a former KGB spy. The two men have exchanged public jibes in campaign-like appearances, fuelling speculation that Medvedev is positioning himself to seek a second term.
Medvedev sought to play down talk of a rift by saying he and Putin were like-minded partners with similar strategies. "But that doesn't mean we agree on everything. It must not be that way. That would be very boring and simply wrong," he said.
In another remark that could be seen as taking a swipe at Putin, Medvedev said: "No one comes to power forever. People who have such illusions usually end badly."
Medvedev could be signaling he has ambitions to be seen as a viable candidate for a second term, but political analysts say the decision on who will run still lies squarely with Putin.
MEDVEDEV SPELLS OUT DIFFERENCES
In comments that differentiated him from his mentor, Medvedev called for modernization to diversify the $1.5 trillion economy away from reliance on oil and gas revenues, 20 years after the collapse of the Soviet Union.
"As far as I understand, he (Putin) believes modernization is a calm, step-by-step process. I think we have the chances and the energy to conduct modernization more swiftly without damage to what has already been done, and to achieve good results."
Medvedev also differed with Putin on the case of oil tycoon Mikhail Khodorkovsky, jailed for theft and money laundering after trials criticized by the West as politically motivated.
Khodorkovsky, once Russia's richest man, was arrested in 2003 after falling foul of the Kremlin during Putin's presidency, and his oil company was brought to its knees by back tax claims. Its main assets were sold off by the state.
Asked whether it would be dangerous for society to release him, Medvedev said: "Absolutely not dangerous at all."
Putin has compared Khodorkovsky to U.S. gangster Al Capone, and said in December that he was a thief who should be in jail.
PUTIN IS MAIN POWER BROKER
A majority of Russians still regard Putin as the country's paramount leader. President from 2000-2008, he has sought this month to broaden his political backing before a parliamentary election in December and the March 2012 vote.
But opinion polls suggest Medvedev has been gaining on Putin in terms of trust and popularity. A poll released on Wednesday by the independent Levada Center showed Medvedev's approval rating in his job was equal to Putin's this month, at 69 percent, for the first time since he took office.
Medvedev's remarks were unusually bold but analysts have cautioned against reading too much into the two leaders' public comments on the presidency, and many suggest moves are being carefully orchestrated in the run-up to the election.
Most analysts say the decision depends on Putin because he remains Russia's most popular politician in opinion polls and has vast influence and clout. Some suggest Medvedev would be committing political suicide if he sought to challenge Putin.
In other comments that appeared intended to convey strength, Medvedev said Russia would increase its nuclear strike capabilities if Washington did not heed its concerns over a planned missile shield for Europe.
"It would be a very bad scenario. This would be a scenario that would throw us back into the Cold War era," he said.
He also criticized Putin's deputy, Igor Sechin, over the collapse of a $16-billion share swap and Arctic exploration deal between Rosneft and BP.
(Reporting by Moscow bureau; writing by Timothy Heritage; Editing by Jon Hemming)