"We informed Igad that we rejected the chairmanship of Kenya in the Sudan crisis committee because Kenya was not neutral," the foreign ministry said.

The pan-Arab Al Arabiya TV channel quoted Sudan's foreign ministry as saying "the statements of senior Kenyan officials and the behaviour of its government confirmed that it adopts the positions of Rapid Support Forces (RSF), shelters its members and provides them with various types of support".

Kenya said it was yet to receive a formal communication of the rejection.

Foreign Affairs Principal Secretary Korir Sing'oei said the appointment of Kenyan President William Ruto to lead the team "was arrived at by the Igad summit and can only be vacated by the summit".

Igad appointed Mr Ruto as the chairman of its delegation, that also has representation from Ethiopia, South Sudan and Djibouti, during the bloc's summit on 12 June.

Mr Ruto has been critical of the war in Sudan, once saying that the rival generals should "stop the nonsense".

He has met envoys of both the Sudanese army and RSF in the Kenyan capital, Nairobi.

Clashes between Sudanese army and RSF have entered a second month with no end in sight.