The Magpies had a brilliant start to the new season, however a run of six defeats in seven top flight games has seen them slip to 16th in the Premier League and only two points off the relegation zone.
Neville now says that Rafael Benitez’s side could find themselves back in the Championship next year unless they bring in some new players in January.
“I think what he is trying to say is sell the club before January because if they don’t strengthen in January they will get relegated,” Neville said on Match of the Day.
“That team has got Championship quality and Championship players.
“They need to bring four or five players in – not just one or two – of Premier League quality.
“The instability is helping nobody.
“You would hope that if someone puts a new bid in that the owner would accept it and the club can move forward.”