The Georgian parliament has unanimously approved limits to the president's powers at an extraordinary session.
The constitutional amendments remove the president's right to fire or appoint a prime minister or cabinet without the parliament's approval.
The March 25 move is seen as a breakthrough that could lower tensions between President Mikheil Saakashvili and Prime Minister Bidzina Ivanishvili.
The two leaders must share power until Saakashvili's second and final term ends in October.
They have been locked in a power struggle since Saakashvili's United National Movement lost October parliamentary election to Ivanishvili's Georgian Dream coalition.
Several former Saakashvili government officials have been arrested and thousands of his party's supporters interrogated in the past three months for alleged wrongdoing.
The investigations have drawn warnings from European diplomats about the use of selective justice and the persecution of political opponents.
Based on reporting by Interfax and AFP