The midfielder had been due to return to training on Monday following a three-week ban imposed after a training ground altercation.
However, Rangers released a statement on Sunday morning to say that Barton must serve a further week’s suspension as part of “a formal disciplinary procedure”.
He has been told to stay away from Ibrox and the club’s training ground at Auchenhowie.
It is now looking increasingly unlikely that the two parties can be reconciled, despite the fact Barton is contracted to the Ibrox club until the end of next season.
It is understood the player will expect his contract to be paid in full if he leaves Rangers, which could cost the club up to £2 million.
The Rangers statement said: “Joey Barton has been informed that his suspension by the club has been extended by one week.
“This is part of a formal disciplinary procedure and Joey has been instructed not to return to Ibrox or Auchenhowie until further notice.
“Neither party (the club and player) will make any further statement or comment.”
Barton was involved in an altercation in training last month in the days after Rangers lost 5-1 to Celtic in the first league meeting between the clubs in four years.
The club banned the player who was reported to have spent last week training in Qatar in a bid to be fit for his return from suspension.
Barton, meanwhile, has until Wednesday to respond to an SFA charge of placing 44 bets on football matches. If found guilty he is likely to be suspended by the governing body.