The 24-year-old Frenchman has been in talks over a new deal, and has not signed one despite having a new contract offer on the table for a number of weeks.
Barcelona have grown increasingly frustrated at the lack of progress on the deal and currently stand to lose him on a free transfer at the end of this season.
Contract rebel Ousmane Dembele has been told to leave Barcelona 'as soon as possible'
The 24-year-old has refused to commit to a new deal despite months of negotiations
But the club have now taken action after confirming that he is not part of the squad that has travelled to Athletic Bilbao for their round of 16 Copa del Rey clash on Thursday evening.
Sporting director Mateu Alemany slammed Dembele for a lack of commitment to the club and confirmed talks with his representatives started back in July.
'We understand Dembele's decision is to not continue (at Barça) and we've communicated our decision (to leave him out),' Alemany said.
'We want players that are committed to the club and we have told him he has to leave the club as soon as