Former Newcastle United midfielder Joey Barton has predicted that Rafael Benitez will leave his job as manager before Christmas.

The Spaniard has admitted that he is unhappy with the club's transfer activity this summer, having seen the arrivals of five new players.

After the Magpies earned promotion to the Premier League from the Championship last season, owner Mike Ashley claimed that Benitez would have funds to recruit the players that he wants.

In a recent interview with Sky Sports News, however, the Sports Direct businessman acknowledged that he cannot compete financially with some of England's elite, including Manchester City.

Barton, who played for Newcastle between 2007 and 2011, believes that it is only a matter of time before Benitez walks away over disputes with the hierarchy.

"Newcastle is a great club, but the owner causes a lot of problems. It's his way or the highway. I can't see Benitez staying there until Christmas," the midfielder told talkSPORT.

"Ashley's interview on TV was silly because it draws everybody in and makes it a soap opera because Rafa has to responded and has to take a side.

"I believe Benitez wants to go. His body language says Ashley has not come through with what he wanted this summer, and that means he feels he won't have the opportunity to establish Newcastle in the top half of the Premier League.

"It ends one of two ways - either the owner leaves and gets the money he wants for the club, or the manager will go because he won't give him the finances he feels is necessary to compete in the Premier League."

Benitez took over at Newcastle in March last year.