The Magpies' top-flight status hangs in the balance as Rafael Benitez's side sit 19th in the Premier League table, three points adrift of safety with a game in hand.
"Oh it's massive that Newcastle stay in the Premier League – massive," the 42-year-old told The Chronicle. "It's going to be a huge setback if the club is relegated.
"For the city, for the club, for the fans, it will be a disaster."