If approved by the referendum vote, presidential elections would be held November 2019.
On Thursday, Turkish Justice Minister Bekir Bozdag said that the referendum on constitution amendments would likely to take place on April 16.
Turkish President Recep Tayyip Erdogan on Friday rubber-stamped controversial constitutional changes that will boost his own powers, paving the way for a referendum on the legislation in April.
The changes would hand wide-ranging executive powers to the president, and the post of prime minister would be abolished. In 2014, he became president after having been prime minister since 2003.
They would allow Erdoğan to consolidate his authority as both the head of government and head of state, eliminating the role of the prime minister.
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There has been a particular crackdown on members of the opposition, academics, journalists and rights activists since a failed military coup in July previous year, after which the government declared a state of emergency.
Erdogan's supporters say the changes are necessary for effective government and to avoid fragile and unstable coalitions that were a feature of Turkey's political scene in the past.
Citing a well-known saying of Mustafa Kemal Ataturk, the republic's founder, Erdogan said: "There is no defense line, but defense territory".
The Turkish parliament sent the constitutional amendments for the President's approval on 2 February, 12 days after it passed the parliament by exceeding the 330-vote threshold to bring it to a referendum. The president-elect will not be obliged to be a non-party nominee any more.
The new 18-article constitution would create an executive presidency similar to the system in the United States and France.