Ousmane Dembele has reacted with fury after Barcelona director of football Mateu Alemany ordered the winger to find a new club "immediately".

French winger Dembele has struggled at Camp Nou since joining from Borussia Dortmund in 2017 for an initial €105million.

A string of injury setbacks have hampered his progress, although Barca head coach Xavi recently claimed Dembele could become the "best in the world" in his position.

Dembele's contract runs until the end of the season, meaning this month's transfer window could be the last opportunity for the club to get back any money on their investment.

Barcelona do not want to lose such an expensive signing on a free transfer, and to that end they have been looking to extend his deal, but Alemany said all offers to Dembele "have been continuously rejected by his agents".

Alemany added, speaking to Barca TV on Thursday: "It seems obvious that the player does not want to continue at Barcelona and is not committed to our future project."

This has incensed Dembele, with Alemany going on to say: "We told him and his agents that he must leave the club immediately because we want to have players committed to the project. We expect a transfer to take place before January 31."

Dembele has been linked with clubs including Liverpool, Paris Saint-Germain and Newcastle.

Responding to Barcelona's stance, Dembele issued a long statement on Instagram, saying he would not be "giving in to any blackmail".

The 24-year-old said he had put up with four years of reading lies about himself, declaring that claims had been made "with the sole purpose of harming me". He said it had been a mistake that he had not spoken out sooner.

"From today, I will answer with sincerity and without giving in to any blackmail," Dembele wrote. "I am 24 years old and like any man, I have faults, imperfections. I have known complex moments, injuries, I have been affected by COVID. Without any training, the coach called on me and I always answered present... without batting an eyelid.

"I appreciate the chance to do the best job in the world. Furthermore, my message is clear. I forbid anyone to pretend that I am not involved in the sports project. I forbid anyone to attribute to me intentions that I never had. I forbid anyone to speak in my place, [or] in place of my agent in whom I have complete confidence.

"Still under contract, I am fully concerned and at the disposal of my club, my coach. I have always given my all for my team-mates as well as for all the supporters... and this won't stop now."

Xavi has also told Dembele to sign or be sold, and the player who was acquired after the big-money departure of Neymar to Paris Saint-Germain may have kicked his last ball for Barcelona. He was left out of the squad for Thursday's Copa del Rey last-16 tie with Athletic Bilbao.

Former Barcelona forward Antoine Griezmann responded with fire and heart emojis to Dembele's passionate statement.

"I am not a man who cheats and even less a man who has a habit of giving in to blackmail," Dembele added.

"As you know, there are negotiations. I let my agent take care of this, it is his field. My field is football, simply playing football, sharing moments of joy with my team-mates, with our supporters. Above all, let's focus on the essentials: WINNING."