The 43-year-old succeeded Jurgen Klopp at Signal Iduna Park, but his contract was cut short after reportedly falling out with the club’s board. He signed off with a trophy in Saturday’s DFB Pokal triumph.
Tuchel set up a Twitter account on Tuesday to pay tribute to the club.
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"I am grateful for two beautiful, eventful and exciting years. Too bad that it does not go on," he wrote in German.
"Thanks to the fans, to the team, to the staff and to all who supported us."
Kurze Umarmung: Hans-Joachim Watzke und Thomas Tuchel
Image credit: Getty Images
The club said Tuchel's departure followed a meeting with the board, including chief executive Hans-Joachim Watzke.
"As the employer, Borussia Dortmund will not express itself as to the background of the separation which is the result of a long process and is supported by all the club committees," said the club, asking for the decision not to be judged on rumours.
"BVB attaches great importance to the fact that the cause of the separation is by no means a disagreement between two persons," it added.
"The well-being of the club Borussia Dortmund is more than about just sporting success and will always be more important than individuals and possible differences between them." (
German publication Bild claim Tuchel's compensation package will cost Dortmund around £2.5 million.
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