From Andrei Tarkovsky: Interviews, edited by John Gianvito:

“The color is pretentious, quite unlike Antonioni usually, and the editing is subservient to the idea of color. It could have been a superb film, tremendously powerful, if only it has been in black-and-white, Antonioni wouldn’t have gotten high on pictorial aesthetics, he wouldn’t have been so concerned with the pictorial side of the film, he wouldn’t have shot those beautiful landscapes, or Monica Vitti’s red hair against the mists. He would have been concentrating on the action instead of making pretty pictures. In my view the color has killed the feeling of truth.…