"FC Internazionale Milano can confirm that Radja Nainggolan has been temporarily suspended from football activity for disciplinary reasons," said the statement.
The club have given no further details of the reasons behind the suspension but according to the Italian press, the action has been sparked by the 30-year-old's habit of turning up late for training.
His late arrival on Sunday morning was the last straw, says Corriere dello Sport.
The Belgian, who started in Saturday's draw against Verona, could miss the Serie A clash with Napoli on Wednesday as well as the game against Empoli on December 29 -- the last two matches before the winter break.
Since his arrival from Roma in the summer, Nainggolan has experienced a difficult start to the season, punctuated by minor injuries.
He made the front page of the Italian sports press earlier in the week as the alleged victim in a fraud case.