On Monday, he appointed his son-in-law, Berat Albayrak, to head a newly formed treasury and finance ministry, sidelining previous office holders in the process.
His appointment - and the absence of familiar, market-friendly ministers from the cabinet - has sent the lira sharply lower.
Mr Erdogan has largely ruled by fiat since 2016, when he imposed a state of emergency on the country in response to a failed coup attempt against him.
Western allies and rights groups decry what they say is increasing authoritarianism and a push toward one-man rule.
During the North Atlantic Treaty Organisation summit, Erdoğan is expected to hold a bilateral meeting with U.S. President Donald Trump, where he is expected to discuss the recent strained ties between Ankara and Washington, particularly the U.S. partnership with PKK's Syrian affiliate, the People's Protection Units (YPG) and the extradition of Fetullah Gülen, the leader of the Gülenist Terror Group (FETÖ), who is the mastermind of the failed July 15, 2016 coup attempt in Turkey.
Erdogan has described high interest rates as "the mother and father of all evil", and said in May he would expect to wield greater economic control after the election. Investors, who have warned that the credit-fuelled economy is overheating, want to see decisive interest rate increases to tame double-digit inflation.
In a signal of those differences, 22 heads of state were scheduled to attend the inauguration, but none from western powers such as the US, Germany, France or the UK.
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Zsa Zsa died in her sleep , according to her owner, Megan Brainard of Anoka, Minnesota, who called the pup's death "devastating". Ms Brainard said children used to sometimes shake that tongue as if giving a handshake to a paw.
"We are embarking on this road by using this opportunity as best we can for a strong parliament, strong government and strong Turkey", he said.
Marc Pierini, a former European Union ambassador to Turkey and visiting scholar at Carnegie Europe, said Erdogan's new powers effectively make him a "super-executive president".
Erdoğan is also expected to hold meetings with French President Emmanuel Macron and British Prime Minister Theresa May. "Obviously it is going to be a step down in capacity compared to Simsek".
The most popular and divisive leader in modern Turkish history, Erdogan pledged there would be no retreat from his drive to transform Turkey, a deeply polarised nation that is both a North Atlantic Treaty Organisation member and, at least nominally, a candidate to join the European Union.
Erdogan´s supporters see the changes as just reward for a leader who has put Islamic values at the core of public life, championed the pious working classes and overseen years of strong economic growth. "There is no stopping for us until we bring Turkey - which we saved from plotters, coupists and political and economic hitmen, street gangs and terrorist organisations - to among the top 10 economies in the world", he said. The government says these measures are necessary given the security situation.
The decree did not state an alternative term length or re-appointment process for the central bank governor, or what new requirements for deputy governors would be.
It was also announced in the Official Gazette that Erdogan had appointed ground forces commander general Yasar Guler as the new chief of the general staff, replacing general Hulusi Akar, who was appointed defence minister in the new government.