Turkish President Recep Tayyip Erdogan has started campaigning for constitutional reforms that would greatly expand the powers of his office.
The move comes hours after a vote in parliament cleared the way for a national referendum on the issue.
Speaking in Istanbul on Saturday, he hailed the assembly's early-morning decision and said "God willing the people will give the true decision, the final decision" that he says would catapult Turkey to a stronger position.
After nearly two weeks of acrimonious debate, Turkey's parliament passed the constitutional reform package, which now needs to be approved in a referendum.
Supporters say the changes would strengthen Turkey, opponents say it entrenches one-man rule.
A public vote on the issue is expected by mid-April, according to officials of the ruling Justice and Development Party, or AKP.
The referendum decision marks a victory for Mr Erdogan, a polarising but overall popular figure who has long advocated a strong presidency that would turn Turkey into a powerhouse.
The ruling party says a presidential system would enable the country to surmount a broad array of internal and external security threats.
Critics fear the changes will concentrate too many powers in the hands of Mr Erdogan, who is accused of authoritarian behaviour and has already established a de-facto presidential system since coming into the office in 2014.
They say the reforms will erode the few existing checks and balances on government.
In addition to changing the system of government, the reform bill allows the president to keep ties with his party and to restructure the nation's highest judicial body.
It increases the number of seats in the assembly to 600, lowers the minimum age for lawmakers to 18 and foresees simultaneous parliamentary and presidential elections every five years.
Kemal Kilicdaroglu, head of the opposition Republican People's Party, condemned the outcome in a speech early on Saturday, saying parliament had "handed over its own authority" and "betrayed" its history.
He vowed to lead a "struggle for democracy" to get the changes rejected in the referendum.
During nearly two weeks of heated debates in the assembly on the topic, lawmakers traded barbs and came to blows on more than one occasion. Three legislators were hospitalised and two of them returned to parliament to vote in wheelchairs.
The parliamentary vote comes six months after a violent attempt to unseat the Turkish president failed on July 15 and ended with the masses rallying to defend him.
Since then, the government has launched a massive crackdown against alleged critics.