Steven Spielberg has revealed that actor Daniel Day-Lewis put in an ''incredible'' amount of work in preparation for his role in 'Lincoln'.

The director of the drama movie was impressed with Daniel's extensive research for the role of the 19th century US President, but said that he had come to expect nothing less from the actor.

He said: ''Daniel does incredible preparation when he tackles any role. He delivers Lincoln as I imagine''.

Spielberg confessed that the actor's knowledge on Lincoln could not be paralleled even by himself.

He added to Hit Fix: ''[Daniel] really honoured Lincoln by reading so much about him, even more than I ever did.

''He came up with his interpretation based on everything he read and everything he experienced.''

The movie - which also stars Joseph Gordon-Levitt, Jared Harris and Tommy Lee Jones - focuses on Abraham Lincoln's presidency and his struggle to pass the 13th Amendment against the backdrop of the US Civil War.

Spielberg said he tried to ''get a little bit of knowledge of history and a little bit of context'' to depict the story.