The African Union (AU) has urged its members to "speak with one voice" against criminal proceedings at the International Criminal Court against sitting presidents.
The 54-nation organisation said it was disappointed that a request to the United Nations Security Council to defer the trials of Kenya's leaders had not yielded the "positive result expected".
Only Botswana has opposed the AU's position, which was made in a statement on Saturday following an Ethiopian summit attended by 34 leaders.
Kenya's president, Uhuru Kenyatta, and his deputy, William Ruto, face charges of crimes against humanity at the ICC in The Hague for allegedly orchestrating post-election violence in which more than 1,000 people died. Both men deny the charges.
Last November, the Security Council rejected an AU demand to suspend the ICC trial of the two leaders. Guatemala's UN ambassador Gert Rosenthal said the attempt to suspend the trial was an act of "contempt" against countries that had sought to help Africa with peacekeeping troops and efforts to boost justice in the continent.
Eight Security Council nations, all ICC members or supporters, including Britain, France and the United States, abstained to ensure the failure of the resolution.
The resolution got seven votes, two below the number needed to pass in the 15-member body.
It was the first time in decades that a Security Council resolution failed in such a way without a veto by one of the permanent members.