The Catalan giants' director of football Mateu Alemany said on Thursday the 24-year-old was refusing to sign a new contract.
Manager Xavi is said to have been left 'speechless' by Dembele's wage demands and the France international has broken his silence.
He posted to Instagram: "As of today it's over. From today, I will answer honestly, without giving in to any kind of blackmail. I am 24 years old and like every man I have flaws, imperfections.
"I have lived through complex moments, injuries, Covid has affected me.
"Without the slightest training session, the coach has requested me and I have always complied without question. Perform as well as I gave always done because it is my passion.
"I am fully aware of my luck to dedicate myself to the most beautiful job in the world."
Since arriving from Borussia Dortmund for £105 million in 2017, Dembele has been ravaged by injury issues.
He's never nailed down a starting place under a number of managers, with some questioning his attitude.
Dembele said he won't 'give in to blackmail' and is available to play.
He continued: "I forbid anyone to give the impression that I am not involved in the sports project.
"I forbid anyone to attribute intentions to me that I have never had. I forbid anyone to speak to me or my representative, whom I fully trust. Still under contract, I am fully involved and at the disposal of my club, my coach.
"I have always given everything for my colleagues and also for all the partners. It is not now that is going to change. I am not a man who cheats and even less a man who has a habit of giving in to blackmail."
The Blaugrana are desperate to lower their wage bill and have already loaned Philippe Coutinho to Aston Villa.
Oscar Mingueza is in talks with Valencia and Barcelona continue to look for a permanent move away for Samuel Umtiti.
Dembele didn't feature at all in Barcelona's 3-2 loss to Athletic Bilbao on Thursday evening, which saw them eliminated from the Copa del Rey.
Barcelona sit sixth in La Liga and return to action against Alaves on Sunday.
Featured Image Credit: Alamy
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