The Gabon striker, who was dropped for Saturday's 3-0 Premier League win over Southampton, will not be considered for Wednesday's game against West Ham.

"We have made this decision that unfortunately is a really tough one," said Arteta.

"If I had to choose I wouldn't like to be sitting here talking about it, but we had to do it.

"When we have to make that decision, it's because it's the right one to defend the interests of the football club."

Arteta has not disclosed how Aubameyang broke the rules, but The Athletic reported

that he returned late from an authorised trip abroad.

Aubameyang was dropped for disciplinary reasons in March, missing the win over rivals Tottenham for a "breach of pre-match protocol".

Asked when Aubameyang might return to the squad, Arteta said: "For now, it's been a lot to digest and a really difficult decision to make, so we need a bit of time.

"It was really hurting and he needs a bit of time to heal."

On his relationship with Aubameyang, Arteta said: "Since I have been here, really good - that's what is painful."

Aubameyang took over as captain in November 2019 after midfielder Granit Xhaka was relieved of the job by then boss Unai Emery.

In a statement Arsenal said:

"We expect all our players, particularly our captain, to work to the rules and standards we have all set and agreed."

Aubameyang, who joined Arsenal for £56m from Borussia Dortmund in 2018, signed a new three-year contract last year.

This season he has scored only four goals in 14 league games and none since 22 October.

Arsenal are sixth in the table, 12 points behind leaders Manchester City.

Arteta said he told Aubameyang "face-to-face" about the decision, but the Spaniard did not say who would replace him.

"We have the leadership group and the different players nominated to be captain - we will follow that," he said.

"It is a really unpleasant situation and it is not the moment to make any rash decision.

"They (the dressing room) have accepted the decision. They know because they have committed to it and they have demanded that we want to take our culture, our demands, who we want to be as a club and how we want to represent this football club, to a different level.

"When those standards are not met you know that you cannot participate in our daily basics."

Analysis

George Cummins, BBC Radio 5 Live

This is very a big call from Arteta. He has always talked of "non-negotiables" and he must feel Aubameyang has crossed the line turning up late twice in a year.

Last Thursday Arteta said there was no desire to sell Aubameyang in January: "We have never discussed something like this. When players are having difficult periods what we have to give is support."

Since then, Aubameyang has been stripped of the captaincy and dropped from two Premier League matches. Having lost the captaincy and his place in the starting XI, there's every chance Aubameyang might want to leave and Arteta will not stand in his way next month.

As for replacements, Alexandre Lacazette will probably be captain against West Ham. Xhaka is a leader at the club but I'm not sure that would go down well with the Arsenal fans after he was stripped of the captaincy. Kieran Tierney and Gabriel would be the fans' favourites.