The World Anti-Doping Agency (WADA) will review the reasons behind the three-month ban handed to Chinese Olympic swimming champion Sun Yang and decide whether to appeal the decision to the Court of Arbitration for Sport (CAS).
Sun, winner of two gold medals at the 2012 London Olympics, served the suspension earlier this year after testing positive for the banned stimulant trimetazidine during the national swimming championships in May.
"WADA will review the reasons for the decision and subsequently decide whether or not to use its independent right of appeal to the Court of Arbitration for Sport," WADA said in a statement on Wednesday.
"In order to protect the integrity of the case, and to respect the proceedings of the case at hand, WADA will make no further comment at this stage."
The China Anti-Doping Agency (CHINADA) could have imposed a longer ban but said it decided on three months because Sun had been given medication, normally used to combat angina, by a doctor to treat a heart issue and was unaware it had been added to WADA's banned list this year.
Sun did not mention the suspension in Incheon at the Asian Games in late September, where he won three gold medals, and CHINADA said it did not immediately announce the sanction because it only reveals positive tests every three months.
The 22-year-old has also won five world titles, holds the world record for 1500m and is one of China's best-known and controversial sportsmen.