They have sent a letter to IOC president Jacques Rogge and said that Adidas should no longer enjoy an exception to the rule limiting logo space to a certain number of square centimetres on athletic uniforms, the German-based Handelsblatt reports.

Adidas is allowed to place the three stripes along uniforms because they are considered design elements and not an actual brand logo such as Nike’s “swoosh”, reports the newspaper.

But rival manufacturers object, saying it allows Adidas greater prominence as an Olympic sponsor.

Adidas said it was surprised by the allegations, saying that sponsored Olympians have worn the three-stripe design for 40 years.