A German auction house intends to sell three watercolour paintings attributed to Nazi leader Adolf Hitler at the start of next month.

The works, depicting cottages, mills and churches nestled in rural landscapes will go under the hammer on Sept. 5, Weidler's auction house in Nuremberg said.

"They're very neutral paintings," Kerstin Weidler told Reuters. "The white church picture is drawn very well in his style -- of course he didn't make it into the Academy of Fine Arts," she added.

The three paintings are dated from 1910 and 1911 and originate from Vienna where Hitler spent several years as a struggling artist. He then joined the army and fought in World War One.

One of the paintings, "White church in the Wachau", was authenticated in 1963 by the late Peter Jahn, a renowned expert on Hitler's early pieces. "He ranked it as among Hitler's chief works," Weidler said.

Although the precise number of works by Hitler is unknown, Weidler said there were an estimated 723 pictures including sketches in existence.

The auction house is expecting a five figure sum for each picture. Earlier this year they sold two other watercolours by Hitler for a total of 32,000 euros ($45,530).

Weidler said the potential purchasers range from people with an academic interest in Hitler to those with a business background.

"They're not bought by neo-Nazis or for a glorification (of Hitler)," she said.