Tom Hanks has described Steven Spielberg as a ''guerrilla filmmaker''.

The Oscar-winning actor has previously worked under the helm of the director in 'Saving Private Ryan', 'Catch Me If You Can' and 'The Terminal', as well as producing several projects together, and has now teamed up with the 70-year-old moviemaker again on 'The Post', and likes the spontaneous way he works.

Speaking on 'The Late Show with Stephen Colbert' about Spielberg, Tom said: ''He just wants to figure it out as he goes along. He's almost like a guerrilla filmmaker. He has the set, he has the space and he wants to fill it with something he hasn't imagined before. I don't mean to [say] that he's not prepared -- he's the most prepared man in the world.''

But the 61-year-old actor's co-star Meryl Streep - who portrays Kay Graham in the movie - was ''mad'' he didn't warn her about Spielberg's directing method.

He added: ''She [Meryl] was mad at me because I didn't tell her Steven doesn't rehearse.''

Tom joked the 'The Devil Wears Prada' actress is ''high maintenance'', but then admitted he had actually found it ''scary'' how down to earth she was on the set.

He quipped: ''Can I just say, 'High maintenance Meryl Streep?' Look, the shoes alone, man. No, I am so joking.

''You know what's scary about Meryl? She comes in and does it just like everybody else does. You're expecting French horns before she enters the stage.

''You expect a guy in livery to come out: 'Ladies and gentlemen, the actress known as Meryl Streep.' And she comes in and waves to the crew the way the royals used to.''