The Gabon international will also be not considered for selection for Wednesday’s league game at home to West Ham United, the club added.
“We expect all our players, particularly our captain, to work to the rules and standards we have all set and agreed,” Arsenal said in a statement.
“We are fully focused on tomorrow’s match.”
Arsenal manager Mikel Arteta dropped Aubameyang from the squad that beat Southampton 3-0 at the weekend due to a disciplinary breach, but the Spanish boss had declined to reveal exactly what the striker had done.
The Athletic reported that Aubameyang was dropped after returning late from a trip abroad.
Alexandre Lacazette led the team against Southampton in Aubameyang’s absence.
Aubameyang, who signed a new three-year contract with the north London club last year, has struggled this season, scoring only four Premier League goals — the last of which was in October against Aston Villa.
The 32-year-old had been dropped before for disciplinary reasons, with Arteta excluding the striker from their 2-1 derby win over north London rivals Tottenham Hotspur last season.
Arsenal are sixth in the league standings on 26 points after 16 matches, two points outside the top four.