The Court of Arbitration for Sport has revealed that the International Association of Athletics Federations has asked for the drugs ban of Rita Jeptoo to be increased.
In September, the Kenyan, who has won a number of marathon races around the world, was handed a two-year suspension after traces of a banned substance were found.
However, the CAS has announced that the IAAF wants the ban to be extended to four years due to "aggravating circumstances".
Jeptoo maintains her innocence and is seeking to overturn the ruling as she targets the World Championships in Beijing in the summer.