In a special party congress convened for the occasion, Erdogan was formally voted back in as the leader of the Justice and Development Party (AKP), exploiting a key change from the controversial April 16 referendum on expanding his powers under a new executive presidency system. He was the only candidate listed on the ballot.

"We were separated, but today we are together again," Erdogan told a crowd of supporters outside the party conference ahead of the vote.

Binali Yildirim, the prime minister and now-former party leader, will be given the consolation prize of the newly created role of vice chairman. 

Despite effectively doing away with his own job and influence, Yildirim was a staunch supporter of the introduction of the executive presidency.

With Erdogan as party leader, a major cabinet restructure is expected, with the Hurriyet daily newspaper speculating that eight to 10 ministers could be moved or replaced.

A slogan at the special congress read "a new breakthrough period: democracy, transformation, reform," hinting at the expected restructuring of government as well as changes to the party's executive in the coming weeks and months.

On Sunday, Erdogan became the first Turkish president to be both party chairman and head of state since the end of the ultra-secular 1950 presidency of Ismet Inonu, the successor of the Turkish state's founder, Mustafa Kemal Ataturk.

Divorce from secular values

Before the constitutional changes Erdogan were pushed through, Turkey's presidents had to sever ties with their political parties in order to be regarded as an impartial head of state.

Erdogan had left the AKP chairmanship in August 2014 after his election as president, having served as prime minister for 11 years.

But last month's referendum on the constitutional amendments had removed the requirement that presidents had to be neutral and removed from political affiliation.

Being allowed in May to rejoin the AKP - the party which he had co-founded in 2001 - was the first major change permitted to take effect after the April 16 referendum.

Other changes from the vote, which Erdogan narrowly won with 51.4 percent, will not come into force until November 3, 2019 - Turkey's next general election.

Among those changes, the roles of the prime minister will be abolished, giving the president sweeping new powers and consolidating major aspects of the executive and judiciary branches under the role. With the AKP firmly rooted in the Islamic tradition, the strengthening of Erdogan's powers means the strengthening of those religious values, signaling a clear departure from almost a century of secular politics as established by Ataturk.

ss/sms (AFP, AP, dpa)