Hundreds of never-seen-before photographs of Adolf Hitler are expected to fetch a six-figure sum when they go under the hammer, an auctioneer said on Sunday.

The photographs, along with negatives, were taken by the Nazi leader's personal photographer Heinrich Hoffmann during the party's rise to power in the early 1930s.

Believed to have been passed on by the photographer himself, they will go under the hammer at a sale in January.

Auctioneer Jonathan Humbert, of J.P.Humbert Auctioneers, said the photos were a previously unseen view of Hitler during his rise to power.

"We've got somewhere around 800 negatives and maybe 600 stills, some from these negatives and other stills that don't have a negative that they were developed from," Humbert said.