Barnett spoke to Sky Sports News about the 29-year-old's future in Spain amid speculation he could be on his way out of the club at the end of the season:
"He wants to stay. I am not sure that Mr Zidane wants him to stay but at the moment Gareth wants to stay.
"He has got a contract, he will quite happily see it out until 2022. He has been and is, in my opinion, one of the top three or four players in the world. This game is a game of opinions and Mr Zidane doesn't think that.
"That is his opinion, he is entitled to it, I won't criticise him."
Barnett was also asked about the possibility of Bale returning to the Premier League, per Sky Sports News: "It certainly is possible, if somebody puts their hand in their pocket and pays us what we think he deserves. It is going to be a lot of money!"
Bale has endured a difficult season at Real Madrid that has once again been disrupted by injuries. He has also struggled for form and has only made 21 La Liga starts.
Zidane said in April that he does not know if Bale has a future at the club beyond the current season after another unimpressive performance against Rayo Vallecano, per Goal.
Marca reported that Zidane has told Bale he is no longer counting on him, as sports journalist Jonas Giaever noted:
Jonas Giæver @CheGiaevara
Marca reporting that Zinedine Zidane has told Gareth Bale that he is not counting on him anymore. Marcos Llorente and Dani Ceballos have both received the same message from Zidane who has started his "one to one"-interviews with the players. They've been told to find new teams https://t.co/r26iLgx5Ns
Real Madrid are expected to spend heavily in the summer transfer window as Zidane looks to overhaul an underperforming squad.
There is a sense that Bale's time at Real Madrid may be coming to an end. He appears surplus to requirements, but his age, injury record and wage demands mean Los Blancos may find it difficult to find a willing buyer.