Robert Havlin has failed in his appeal to the authorities in France over a six-month riding ban imposed after testing positive for a prohibited substance.
Ruling body France Galop said last month the Newmarket-based jockey had returned a positive sample when riding at Saint-Cloud on October 30 and that it would "request the reciprocation" of the imposed sanction by the British Horseracing Authority.
Havlin strongly refuted the findings, saying at the time the ban was announced he was "deeply upset and shocked" by the suspension and that he fully expected to clear his name following what he described as an "outrageous miscarriage of justice".
The BHA confirmed on Thursday afternoon it had been informed by France Galop of the unsuccessful appeal, but that Havlin had the right to apply for the suspension not to be reciprocated.
Spokesman Robin Mounsey said: "The BHA has been informed of the decision by France Galop to suspend Mr Havlin from riding in races for six months. Under the international agreement and the rules, this penalty will be reciprocated when it comes into effect.
"However, the individual involved has the right to lodge an application to the BHA for the penalty not to be reciprocated. Such an application would be considered by the Disciplinary Panel."