"No country, including China, can easily post 8 or 9 percent growth figures this year or in 2013. Therefore, it is not possible for Turkey to post 8 or 9 percent growth figures like the past two years," Erdem Basci told reporters at a roundtable.
"That is why we have landed on the runway. Okay, let's unbuckle our seatbelts, grab our suitcases and continue by road," Basci said.
The central bank and the country's finance minister have previously said Turkey's economy was experiencing a soft landing - a relatively gradual slowdown that does not lead to a collapse into recession.
The government is targeting growth of 4 percent this year, down from 8.5 percent in 2011.
On Thursday, Fitch said it may raise Turkey's long-term rating to investment grade if it makes progress towards its potential growth rate, trims inflation to its target rate and narrows the current account gap.
In a report on the Turkish economy, the ratings agency said the country's soft landing was on track so far, but that its large external financing requirement still left it vulnerable to adverse shocks to the global financial environment.