MOSCOW -

Russia's upper house speaker called Friday for constitutional changes that would allow President Vladimir Putin to remain in office beyond 2008 -- a proposal that was quickly rejected by the Kremlin.

In a speech after his re-election as speaker of the Federation Council, Sergei Mironov said the presidential term should be extended from four to at least five years and that presidents should be permitted to serve more than two consecutive terms.

The March 2008 presidential vote is seen as a key test for Russia's political system, and any change in the law to permit Putin to stay in the job would be seen by the West as a further erosion of democracy.

Kremlin spokesman Dmitry Peskov dismissed Mironov's proposal, saying that Putin opposes any changes in the constitution that would extend his term.

"We proceed from the president's position that it is pointless to change the constitution to extend the presidential term or the number of terms," he told The Associated Press. "This stance of the president remains unchanged."

Several opposition figures also said they doubted that Putin would seek to serve beyond the March 2008 presidential elections.

Putin is approaching the constitutional limit of two straight terms in office. Pro-Kremlin politicians have sought changes in the law to permit Putin to retain power, but Putin has repeatedly said he plans to step down. He has, however, also made statements that appear to leave the door open for a change of heart.

Several analysts and opposition leaders saw Mironov's statement as a declaration of loyalty by a longtime ally, rather than a Kremlin gambit to extend Putin's time in office. At the same time, some analysts say, there appears to be mounting pressure on Putin to stay from some members of his inner circle.

Garry Kasparov, the former world chess champion and opposition leader, characterized Mironov's proposal as "hysterical weeping" by Putin loyalists who could lose their jobs in a change of administration.

"They understand that Putin will not stay on, but they don't know what to do next," he said at a news conference.

Some observers said that Putin has encouraged speculation on the issue.

"In this nation, where there is no real parliament and the Cabinet is weak, a lame duck president would mean anarchy," said Nikolai Petrov of the Carnegie Endowment's Moscow office. "Putin is deliberately uncertain about his plans, and Mironov is taking part in this game which Putin needs."

Mironov leads a new political party, created with the Kremlin's blessing, that made a strong showing in provincial elections earlier this month. The party is expected to perform strongly in December's elections to national parliament.

Others have also urged Putin to run again, but Mironov is one of the most prominent political figures to do so.

"Four years is a short period of time for a large country like Russia. It is necessary to prolong the presidential term in office to five or maybe seven years," Mironov said. He called for provincial legislatures to stage meetings to debate the issue over the next two months, ITAR-Tass reported.

"The final decision, of course, will be up to Vladimir Putin -- maybe he will listen to the voice of the lawmakers," Mironov said, according to ITAR-Tass.