International Criminal Court appeals judges have ordered the original panel to reconsider whether to indict Sudanese President Omar al-Bashir with genocide over Darfur.
The Hague-based court's pre-trial chamber will now have to rule on whether to charge Bashir with "genocide", which already includes seven counts of crimes against humanity and war crimes.
The court charged al-Bashir with seven counts of war crimes and crimes against humanity in March 2009. But judges said there was insufficient evidence to merit charging him with three genocide counts.
Prosecutors appealed the decision. The Arab League last year issued a statement rejecting al-Bashir's indictment, while the African Union has said it will no longer co-operate with the ICC over the arrest warrant.
Appeals judge Erkki Kourula of Finland said Wednesday that that ruling set the standard of evidence "too high" and ordered the judges to look again at filing genocide charges.
But Kourula added that the appeals chamber would not grant the prosecutor's request for a ruling that Bashir was criminally responsible for the crime of genocide.
Bashir has repeatedly dismissed the allegations made by the ICC as part of a Western conspiracy.
The arrest warrant against Bashir was the first ever issued against a sitting head of state by the ICC.
The investigation into Darfur was launched in June 2005 after the United Nations Security Council referred the situation to the ICC.