Kazakh President Nursultan Nazarbaev has signed constitutional amendments transferring some powers from the president to government ministers and lawmakers.
Nazarbaev's office said he signed the amendments into law on March 10.
The Constitutional Council approved them on March 9 after they sailed through parliament, which is dominated by Nazarbaev's Nur Otan party.
The 76-year-old Nazarbaev, who is the only communist-era leader still holding power in a former Soviet republic, proposed the changes on January 26.
He said they would give government ministers more power and responsibility to manage the economy and social issues, while increasing parliamentary control over the government by giving lawmakers the authority to hold votes of confidence in the cabinet.
He said the president's role would become that of a "supreme arbiter."
The changes have prompted speculation that Nazarbaev is preparing for an eventual transition of power in the tightly controlled, oil-producing Central Asian state of 18 million.