He said in March that a mega deal between Turkey and Europe on the reprocessing of refugees would be reviewed after the referendum.
"This constitutional change will bring stability and trust that is needed for our county's development, growth and stability", Erdogan told supporters at the rally.
The newly married Yucel, a reporter for the German daily "Die Welt" who has been imprisoned in Turkey since mid-February, will not be released as long as Turkish President Recep Tayyip Erdogan remains in power, the Turkish president promised on Thursday.
The package of 18 amendments would abolish the office of prime minister and give the president authority to draft the budget, declare a state of emergency and issue decrees overseeing ministries without parliamentary approval.
Burak Bilgehan Ozpek, associate professor of worldwide relations at Ankara's TOBB University, said a "Yes" vote would mean the end of the opposition within the MHP.
The final day of campaigning is taking place in Turkey ahead of a referendum on whether to grant sweeping new powers to the president. He also appealed to voters of other parties to approve the changes so "Turkey can leap into the future".
"On Sunday I think that could be a very clear outcome in favour of "Yes" he said.
The vote has become somewhat of a referendum on Erdoğan himself, who past year survived a failed coup attempt and emerged stronger than ever.
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Turkey has arrested or suspended more than 140,000 people since the coup attempt and has jailed the most journalists out of any country in the world. In 2010, Erdogan's government took several hundred officers to court on charges of planning to overthrow the government. Erdogan blames Gulen for orchestrating the coup attempt. The election process for Turkish citizens living overseas ended on April 9.
Erdogan's supporters argue that a "yes" vote would enable the president to speed up policy implementation that's normally complicated by Parliament.
The president can be elected for two consecutive five-year terms. If the president dissolves parliament, then both parliamentary and presidential elections will be renewed.
Under the existing constitution, Turkey's chief executive is the prime minister, chosen by the parliament. Many believe he has improved services and health care, and given a voice to pious Muslims who at times felt marginalized by more secular governments. When ministers attempted to campaign in European Union countries, there was a clampdown on rallies and Erdogan responded by calling leaders "fascists" and "Nazis". Since an attempted coup in the middle of a year ago, hundreds of thousands of civil servants have been sacked and detained. "We have paid dearly for these delays".
Erdogan and government officials are accused of using state resources and official functions such as openings of infrastructure projects to campaign in favor of the changes.
The main opposition Republican People's Party, or CHP, says it has counted more than 100 incidents of obstructions to the "no" campaign, ranging from physical assault to death threats. If it is approved by the popular vote, the referendum will be the first step toward a more comprehensive reform of the administration in the coming period.
Erdogan will on Friday speak in Konya, the Anatolian city seen as the heartland of conservative supporters who have benefited from his rule. A "Yes" vote would put the country in danger, he said. "Everyone will know their place", he said. "You can not meddle in what happens if "yes" wins or if "no" wins".
"MHP voters feel deceived, they feel they have been fooled", said Sinan Ogan, a leading member of a camp within the MHP that wants to see Bahceli ousted. "Talk about that with the party representatives who did not work".