African countries support the International Criminal Court (ICC) but its chief prosecutor is guilty of double standards, the chairman of the African Union Commission said on Saturday.

Jean Ping's comments came a day after Africa's foreign ministers threw support behind Kenya's bid to defer the investigation of key suspects accused of masterminding the ethnic bloodshed that followed a disputed election in 2007.

That vote, although still to be rubber-stamped by heads of state, is expected to embolden the east African nation to ask the UN Security Council to freeze the investigations for at least one year.

"We Africans and the African Union are not against the International Criminal Court. That should be clear," Ping told a news conference at an African Union summit in Ethiopia.

But, "we are against Ocampo who is rendering justice with double standards," he said, referring to ICC prosecutor Luis Moreno-Ocampo.

The ICC's active cases all target crimes against humanity committed in the African states of Sudan, Democratic Republic of Congo, Central African Republic, Uganda and Kenya.

"Why not Argentina, why not Myanmar ... why not Iraq?," said Ping.

Ocampo has rejected criticism from African states, saying the ICC is only a court of last resort for countries that are either unable or unwilling to try suspects themselves.

The ICC is also conducting preliminary examinations to determine whether it has the jurisdiction to open formal investigations in Afghanistan, Colombia, Georgia, Guinea, Honduras, Ivory Coast, Nigeria and the Palestinian territories.

Ocampo started investigations in the case of Kenya's post-election violence after east Africa's largest economy failed to set up a local tribunal to try suspects.

The ICC's pre-trial chamber is expected to announce by early March whether six suspects - including Finance Minister Uhuru Kenyatta and suspended ministers William Ruto and Henry Kosgey - have a case to answer in The Hague.

Kenya says it is now better placed to hold local hearings after adopting a new constitution in August that was designed to strengthen the judiciary.