“Signed, sealed and delivered - it is now law,” the country’s information ministry writes in a post on X in capital letters.
The country's parliament has previously approved constitutional amendments that extend the terms of office of the president and parliamentarians from five to seven years. Direct presidential elections are also abolished. The right to appoint the president instead falls to parliament.
Critics have described the proposal as a "constitutional coup" that is feared to consolidate the ruling Zanu-PF party's grip on power.
Mnangagwa has ruled the country since 2017, when the military forced the authoritarian Robert Mugabe out after 37 years in power.
