Presidential aide Igor Shuvalov said another candidate might emerge later this year, Russia's RIA Novosti news agency reported.
Presently, two first deputy prime ministers, Sergei Ivanov and Dmitry Medvedev, are seen as Putin's most likely successors.
Putin has declined to identify his choice, saying only that the Russian people will choose his successor.
(RIA Novosti)
Russia Beyond 2008
President Putin is mulling his political future (epa)
THE 2008 QUESTION: President Vladimir Putin's second term of office ends in the spring of 2008. Since the Russian Constitution bars him from seeking a third consecutive term, this event threatens to present a crisis in a country that has a history of managed power transitions. Already, Russian politics are dominated by the ominous 2008 question.
RFE/RL's Washington office hosted a briefing to discuss the prospects of Putin seeking a third term. The featured speakers were RFE/RL Communications Director Don Jensen and political scientist Peter Reddaway of George Washington University.
LISTEN
Listen to Don Jensen's presentation (about 16 minutes):Real Audio Windows Media
LISTEN
Listen to Peter Reddaway's presentation (about 35 minutes):Real Audio Windows Media
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