Turkey's ruling Justice and Development Party (AKP) on Saturday formally launched its campaign for the upcoming referendum on core constitutional changes set to empower the presidency, with a mass rally at a sports arena in Ankara.
The Islamic-conservative party released a jingle with the hook "Of course, yes," and red and white balloons - the national colours - were distributed with the word "Yes" on them.
The constitutional reform package promoted by President Recep Tayyip Erdogan would give wide-ranging new powers to his office. Critics say the moves would weaken parliament, checks and balances and the independence of the judiciary.
Prime Minister Binali Yildirim addressed thousands of supporters in a sprawling speech that lasted well over an hour and was sprinkled with references to key Turkish battles during World War I and Ottoman Sultan Mehmet, who conquered Istanbul.
Yildirim, in an address carried by news channels and the state-broadcaster, pushed the party line that terrorist organizations are opposed to the constitutional changes and were campaigning for a "no" vote.
"The new system will put an end to terrorism, it will destroy terrorism," Yildirim said, according to a transcript from the state-run Anadolu news agency. Erdogan's name, whenever mentioned, drew cheers.
More than 6,500 police and security officials were on guard for the event, Anadolu reported.
Erdogan himself has already been campaigning for the referendum, which is due to take place on April 16.
The country remains in a state of emergency put in place after a failed coup attempt by a faction in the military last year. Opposition campaigners have complained about restrictions affecting their efforts.