The campaign for April's constitutional referendum was declared open by the Supreme Election Board on Thursday.
From Thursday, political parties are officially allowed to campaign on the constitutional changes that could usher in a presidential system for Turkey. A referendum on April 16 will ask the electorate to vote Yes or No to the changes proposed in an 18-article bill.
Parties can campaign until 6 p.m. on April 15.
President Recep Tayyip Erdogan will initiate the Yes campaign with a series of meetings in southern Kahramanmaras province on Friday.
The main opposition Republican People's Party (CHP) plans to start its No campaign with a media launch on Monday and meetings in major cities such as Istanbul, Ankara and Izmir.
Turkish nationals overseas will be able to vote between March 27 and April 9 at polling stations in embassies and consulates as well as at Turkish ports and airports. These votes will be tallied in Turkey on referendum night.
Constitutional reform has been under discussion since then-prime minister Erdogan was voted president in August 2014.
The bill was passed by parliament in January, with 339 votes in favor -- nine more than needed to put the proposals to a referendum.
The proposals would hand wide-ranging executive powers to the president and abolish the post of prime minister. The president would also be allowed to retain ties to a political party.
Other changes would see the minimum age for parliamentary candidates reduced to 18 and the number of deputies rise to 600. Simultaneous parliamentary and presidential elections for a five-year term would be held in November 2019 under the new constitution.
Reporting by AylinSirikli Dal; Writing by Emin Avundukluoglu