One of cycling's major sponsors claims the International Cycling Union has been "complicit" in sweeping the Lance Armstrong doping scandal under the carpet.
Jaimie Fuller, chairman of the Australian sportswear firm Skins that has invested around 10million US dollars into the UCI over the last five years, says the scandal has caused reputational damage to the sponsors.
The firm has served a legal notice on the UCI claiming 2million dollars (£1.25m) in compensation.
Fuller said: "This is a ground-breaking move and it's one of those situations that could become case law for the future.
"When a sport is in trouble you look to the international federation to help it through. It's a pretty rare situation where the international federation is actually complicit in what was going on."
Fuller also claimed that UCI president Pat McQuaid and his predecessor Hein Verbruggen needed to accept responsibility for the failure to deal with Armstrong, who was last month stripped of his seven Tour de France titles.
"These two gentleman have sat at the top of world cycling for 22 years and they need to be accountable for what they did and did not do," said Fuller.
Meanwhile, British cyclist David Millar says the UCI need to make a full apology.
Millar told the Guardian: "The UCI need to be very careful, because the momentum is rolling too fast for them to control it. Just as with Lance Armstrong, we'll reach another tipping point soon. I sense the same looming crash with the UCI - unless they act decisively.
"They have to act quickly or they're going to face a total revolt and they'll be out anyway.
"Now there is a public awakening and the UCI will be in real trouble unless they make a full apology. There seems to be some unbreakable alliance between McQuaid and Verbruggen. Pat needs to cut that cord and move forward. He needs to wake up to the fact that some revolutions become unstoppable."
The UCI released a statement in which it stated steps it has taken since the Armstrong affair became public, including setting up an independent commission to examine the issues raised.
The statement read: "The UCI can confirm that it has received a letter from the chairman of Skins International Trading AG.
"In the years that Skins have been a sponsor, since 2008, cycling has been a completely different sport from what it was during the period 1998-2005, when tests for EPO did not exist.
"Since the dark period of Lance Armstrong, cycling has been a pioneer in the fight against doping in sport under the leadership of the UCI and this role has been recognised by WADA.
"The UCI is determined to turn around this painful episode in the history of our sport. We will take whatever actions are deemed necessary by the independent commission and we will put cycling back on track.
"While we understand the concerns expressed by Skins, the UCI is determined to work hand in hand with all cycling's stakeholders towards the same goal, which is to safeguard the integrity and future wellbeing of the sport.
"The UCI is determined that this independent commission will just be the start of the process and nothing will be off the agenda."