Opposition leader Raila Odinga has left the country for South Africa to visit his daughter Rosemary in hospital.
Mr Odinga left Jomo Kenyatta airport in Nairobi shortly after 7am aboard aboard Kenya Airways flight destined for Johannesburg.
He will be out of the country for slightly over a week, according to his spokesman Dennis Onyango.
Ms Rosemary has been in a South African hospital for over a week, suffering from a brain tumour, even though doctors said it is not life-threatening.
She is with her mother Ida and younger sister Winnie.