Manchester United winger Nani has arrived in Istanbul to complete a move to Fenerbahce.
Liverpool are set to confirm the appointment of Sean O'Driscoll as assistant manager on Monday.
Newcastle's canny transfer dealings helped secure a fifth-placed finish last season, but the club's success has left them vulnerable to offers for the likes of Cabaye and strikers Demba Ba and Papiss Cisse.
And France star Cabaye reckons owner Mike Ashley must hold firm or risk overseeing a return to mid-table mediocrity.
He said: "Demba scored so many goals for us so it's going to be important to keep him - and keep all the big players.
"I hope the board are going to do the right things to keep them.
"I don't know if we can go higher than last season, but we have to keep doing the right thing."