The email was sent to the DOSB President, the Board of Directors and the Business Council, with the message allegedly signed by DOSB staff.

According to German website Der Spiegel, the email calls for the resignation of DOSB President Alfons Hörmann.

"Under the leadership of the current President, a 'culture of fear' has established itself among the staff in the DOSB," the letter says, according to Der Spiegel.

"Differing opinions are (at best) ironed out and (at worst) exposed.

"And so we are also afraid.

"Fear of having to reckon with consequences under labour law when naming our names, maybe even losing our job."

The letter claims some staff have been brought "mentally and psychologically over the limits of what they could take", while allegations have been made that objects have been thrown at employees.

The environment has reportedly led to several employees quitting the DOSB.

Hörmann is also criticised for having allegedly not worn a mask at meetings in breach of a coronavirus-related mask requirement.

The DOSB Presidium has issued a statement in response to the letter, which the organisation claims has been made from a fake email account.

A statement was signed by Uschi Schmitz, Andreas Silbersack, Kaweh Niroomand, Prof. Dr. Gudrun Doll-Tepper, Dr. Petra Tzschoppe, Jonathan Koch and Britta Heidemann in response to the email.

"We are jointly pursuing the clear goal of value-based action and see an open willingness to communicate at all times as an important component," the statement read.

"We are therefore amazed at the anonymously raised allegations about the current leadership situation in the DOSB and especially against our President, and we reject this style of communication and the path we have chosen via the media.

"Regardless of this, we will thoroughly examine the points of criticism listed.

"We express our unreserved trust and our full support to our President Alfons Hörmann, at the same time we will take the allegations seriously in an intensive exchange with the employees.

"It is our concern to work in a trusting relationship between volunteers and full-time jobs, management bodies and employees for the DOSB and sport in Germany."

A separate statement was also published by the DOSB Board, which is comprised of chair Veronika Rücker, chief financial officer Thomas Arnold, Dirk Schimmelpfennig and Christina Gassner.

The DOSB Board claims it takes the criticism expressed in the letter "very seriously" and says it will "examine the allegations".

However the DOSB Board says it does "clearly reject the criticism of our President Alfons Hörmann".

"The cooperation between the President and the Executive Board is characterised by a very constructive, professional and fair cooperation," the DOSB Board statement read.

"The President and the entire Presidium volunteer every day with great commitment for the DOSB and sport in Germany and we give them the highest recognition and respect for their commitment and their performance.

"From our perspective, we cannot see any behaviour that - as assumed in the open letter - 'lacks any form of respect and decency'.

"The Board of Directors appreciates the close and open exchange with the President and the Presidium and makes it clear that the cooperation between the president and the board of directors is always based on trust and mutual respect."

Hörmann has reportedly claimed executives and employees have distanced themselves from the letter.

The DOSB President has recently come under fire from both the International Olympic Committee (IOC) and the North Rhine-Westphalia Prime Minister Armin Laschet over comments made regarding the 2032 Olympic and Paralympic bid process.

Hörmann reportedly expressed surprise at the early announcement of Brisbane as the preferred candidate.

IOC Future Host Commission chair Kristin Kloster Aasen accused Hörmann of making "incorrect statements", saying the DOSB had opted against entering into the continuous dialogue phase with the Future Host Commission group in February.

Laschet, who has supported the private Rhine-Ruhr bid, said it was amazing that the DOSB had "no sense of what is going on at the IOC."

Stefan Klett, President of the State Sports Association of North Rhine-Westphalia, has now called for Hörmann to resign.

"The non-profit German sport needs trust, transparency and humanity in the pandemic time and a president who has his own affiliates and the grassroots actively listens instead of ignoring them," Klett said, according to RTL.

"After the disastrous repeated Olympic failure, the cut up tablecloth with the IOC, the dilettantism in dealing with the impact on the Vaccination Protection Act, this process breaks the barrel.

"His lack of respect for the employees and, as it were, the popular sports base in the sports clubs harms the important social tasks of the DOSB."