Addressing a joint session of parliament in Astana, the long-serving president suggested transferring some presidential powers to the legislative branch and other measures that he characterized as liberalizing Kazakh politics.
"I propose such constitutional changes that would maintain the presidential form of government for the republic but would expand significantly parliament's powers," he told lawmakers. "In effect, this would transform the presidential model of our republic into presidential-parliamentary."
Nazarbaev also proposed increasing the number of members of both the lower and upper houses of parliament by 38 to a total of 154.
The bill on amendments and addendums to the constitution envisage a reduction in the presidential term from seven to five years.
"It is expedient to reduce the presidential term from seven to five years," said Nazarbaev, who has led Kazakhstan since 1989 and extended his powers and his term in office in a referendum that was widely dismissed by the international community. "This path has been chosen by France, for example. This reform will be introduced after 2012."
Nazarbaev also suggested removing from the constitution a ban on the state's financing of public associations and parties.
Nazarbaev said the proposed changes, if accepted, would be an important step toward modernizing the country.
"Having studied and analyzed world practice, we have chosen precisely the evolutionary path," he said. "We are against a forceful introduction of democracy, especially from the outside. We are not trying to copy anybody, but are doing what our country and our people need."
Lawmakers accepted the bill in its first reading in a joint session later today.
The leader of the opposition National Social Democratic Party, Zharmakhan Tuyakbay, expressed "optimism," saying authorities apparently intend to implement "serious political reforms."
International rights groups and foreign governments have long criticized the Kazakh administration over its suppression of dissent and strictures on political participation and civil society.
Kazakhstan's size and its rich fossil-fuel deposits combine to give it considerable economic and political might in the region.
(RFE/RL's Kazakh Service, Kazakhstan Today, Interfax-Kazakhstan, ITAR-TASS)