Espirito Santo revealed that his relationship with Forest owner Marinakis had changed despite their impressive start to the season.
The Portuguese coach said: "I always had a very good relationship with the owner, last season we were very close and spoke on a daily basis.
"This season it is not so well (between us) but I always believe that dialogue is important because my concern is the squad and the season we have ahead of us. Our relationship has changed and we are not as close.
“I think everybody at the club should be together but this not the reality."
According to The Sun, Forest have already lined up his replacement and will move to bring former Tottenham boss Postecoglou to the club.
It’s understood that Postecoglou is keen on an immediate return to management after being sacked by Spurs at the end of last season.