Turkish President Recep Tayyip Erdogan, who is pushing for constitutional changes that would turn Turkey's political system into a presidential system expanding the powers of his office, has cited Hitler's Germany as an example.

Asked whether the system he wants could exist within a "unitary state", Erdogan told reporters late Thursday that Hitler's Germany was one example in history, among others, where the presidential system had functioned.

Erdogan said: "When you look at Hitler's Germany, you'll see it there."

His words were reported by the Dogan news agency and others on Friday. There was no immediate reaction from opposition leaders.

The existing constitution limits the powers of the president. Critics fear that a presidential system would give far-reaching powers to Erdogan, who has already displayed an increasingly authoritarian tendency.