Russian lawmakers on Friday approved constitutional changes extending the length of presidential terms, a move opponents said could lead to Vladimir Putin's return to the presidency.
   
The lower house of Russia's parliament, the State Duma, overwhelmingly endorsed lengthening presidential mandates from four years to six, with 388 votes in favour and 58 against in the first of three required readings.
   
The Kremlin, in a written explanation, said the changes would "ensure stable and progressive development of the country."
   
The changes "fully accord with international practice" and will "increase the period in which state institutions work most fruitfully" between elections, said Vladimir Pligin, head of the Duma's constitutional affairs committee.
   
The changes, the first ever to Russia's 1993 constitution, were announced earlier by President Dmitry Medvedev and were expected easily to win approval, drawing criticism in parliament only from Communist party deputies.
   
The changes will also increase parliamentary terms from four years to five.
   
Final approval requires the assent of both houses and two-thirds of Russia's regional assemblies.
   
The State Duma is expected to hold the second and third readings on the amendments next week before they move on to the upper house, the Federation Council.
   
There has been speculation that Medvedev, who succeeded Putin as president in May, could use the pretext of constitutional changes to step down early and make way for the return of his mentor.
   
Both men have played down such claims without rejecting them outright.
   
Activists from the opposition Yabloko party mounted a small rally outside parliament, holding up a placard with a quote from Putin: "You should change brains, not the constitution," the Echo of Moscow radio station reported.
   
Predicting economic turmoil ahead for Russia, Vladimir Ryzhkov, a former opposition lawmaker, said in Friday's Moscow Times newspaper: "Putin might try to keep a step ahead of the game once again.
   
"Using pretexts such as the new constitution and the need to strengthen the state in the face of the crisis, he might through Medvedev announce snap presidential and parliamentary elections as early as March or April."
   
Noting that in his own presidency Putin had vowed not to change the constitution, Ryzhkov said: "Medvedev has made no such promises. Now Putin's wish to make elections an even rarer event is being granted by his hand-picked successor."
   
On Wednesday Putin voiced support for the changes, insisting they had no "personal dimension".
   
He added: "As far as who could run for the next term or when, it's too early to say." The response raised eyebrows as it suggested doubt about the next scheduled presidential election date of 2012.
   
Medvedev was cagey when asked about his intentions in an interview with France's Le Figaro newspaper published on Thursday.
   
"I'm still working. Why are you trying to push me into some kind of decision? I can only say for sure that this new term can only apply to a presidential candidate who stands for the post after the passage of the corresponding changes," Medvedev said, according to a Kremlin transcript.
   
In the overwhelmingly compliant parliament on Friday only Communist deputies voiced opposition.
   
"We can't vote for these amendments when the country is ruled by an authoritarian leadership.... It's unacceptable to leave the country's destiny in the hands of a single person," said Communist deputy Viktor Ilyukhin.