Longo, a 59-time national champion who has won the women’s Tour de France three times and claimed a total of 30 medals from the Olympic Games and world championships combined, is one of France’s most popular sports personalities.

But her plans to cap her stunning career with a possible final Olympic appearance in London next year could now lie in tatters.

According to L’Equipe sports daily Longo, 52, faces a ban of “between three months and two years” after being warned three times  by France’s National Anti-Doping Agency (AFLD) for failing to warn officials of her exact whereabouts ahead of random tests.

It said Longo had “infringed the rules concerning athletes’ whereabouts three times during the past 18 months”.

In accordance with strict anti-doping rules professional cyclists are supposed to notify the authorities of their whereabouts on a daily basis, and makes themselves available for testing from the early hours until late at night.

The report said Longo gave insufficient information as to her whereabouts on the first two occasions.

On a third occasion, the United States Anti Doping Agency (USADA) had to report a “no show” after failing to locate Longo at a hotel she was supposed to be staying at during a training camp in  the US several days before the national championhips in June 2011.

Longo has therefore received three official warning from the AFLD, which automatically leads to a sanction.

The AFLD has passed the case to the French Cycling Federation (FFC), which has the power to decide on a ban.

FFC president David Lappartient, speaking to the Infosport+ channel, said Longo risked a sanction.

“She hasn’t taken any banned products but... when you makes three mistakes concerning your whereabouts you are eligible to be sanctioned the same way as someone who has tested positive for banned substances,” said Lappartient.

“Jeannie Longo is currently contesting some (of the circumstances concerning) of her whereabouts. Of course, she still risks a sanction. We are likely to be informed by the AFLD and when  that happens the dossier will go to out disciplinary committee.

“They will decide whether to sanction Jeannie Longo or not, I can’t predict what they will do.”  

Lappartient admitted the affair could tarnish Longo’s career.

“It’s embarrassing for Jeannie Longo because it could cast a shadow over her career and she doesn’t deserve that, and embarrassing for the French Cycling Federation.

“But her case will be treated just the same as any other.”   

Longo was scheduled to participate at the world road race championships in Copenhagen later this month, where she was to ride  the women’s road race and the time trial.

In a statement addressed to AFP the Frenchwoman said she had nothing to hide.

“I’ve been tested more than any other athlete in the world and not once has there been cause for any suspicion on my sporting integrity,” said Longo.

“I’m confident the French cycling federation will treat this matter in an impartial and objective manner.”