The Constitutional amendments, which apply to the next head of state and legislature only, come into law on the day they are published.
Since it was adopted 15 years ago, the Constitution has been amended only once to cut the number of Russian regions from 89 to 83 on March 1, 2008.
Russian President Dmitry Medvedev, who first proposed introducing the amendments during his first state of the nation address in early November, signed them into law in late December, after they were approved by the lower and upper houses of parliament.
Under the Constitution, the approval of at least two-thirds of regional legislatures was also required to extend the current four-year presidential and parliamentary terms. All Russian regions approved the presidential move in December.