Former Russian president Boris Yeltsin has made a veiled criticism of his successor's decision to increase his powers after the Beslan tragedy.
Yeltsin has kept a low profile since he left office
Mr Yeltsin said that the rolling back of democratic rights in Russia would be tantamount to victory for terrorists.
President Vladimir Putin on Monday announced plans to abolish direct elections for regional governors and change voting rules for parliament.
The proposals may need constitutional change, but Mr Putin denies such plans.
However, he said the changes were important to bolster central authority after a series of terrorist acts in recent weeks culminating in the school siege in which more than 300 people died.
Meanwhile Boris Gryzlov, speaker of the lower house of parliament, the State Duma, said the chamber would discuss lifting a moratorium on the death penalty for cases of terrorism introduced by Mr Yeltsin.
"This question has been raised by many members of society,
citizens and deputies," he said, adding that he supported the moratorium. "The situation compels us to
return again and again to this topic."
'Shoulder to shoulder'
In an interview to be published in Friday's edition of the newspaper Moscow News, Mr Yeltsin said Russia should not move away from the spirit or the letter of the constitution he introduced in 1993, and which was approved in a national referendum.
"The stifling of freedoms and the rolling back of democratic rights will mean, among other things, that the terrorists will have won," he said.
The 73-year-old former president said he expected Russia "to stand shoulder to shoulder with other civilised nations" in the fight against terrorism.
BBC Russia analyst Stephen Dalziel says Mr Yeltsin's is the most significant voice of dissent from inside Russia to Mr Putin's plans.
Mr Yeltsin, who appointed Mr Putin as prime minister in 1999 and endorsed his bid for the presidency the following year, said it was "correct and civilised" for a former president to criticise his successor.
The interview came a day after exiled tycoon Boris Berezovsky, once one of Mr Yeltsin's closest allies, called on the former president to speak out about the situation in Russia following Beslan.
Mr Yeltsin had made the mistake of keeping quiet as Mr Putin began to "destroy" everything that he stood for, the tycoon said.