Nairobi: A relative of Barack Obama says the President's step-grandmother suffered minor injuries after a car she was traveling in rolled over.

The relative on Monday said that Sarah Obama was traveling to her home in the village of Kogelo, in western Kenya, when the accident happened on Saturday night.

He said the vehicle lost control and rolled as the driver attempted to overtake a truck near the Kisumu airport. The relative asked not to be named because he is not authorised to speak for the family.

Sarah Obama is the second wife of Obama's paternal grandfather. Obama referred to her as "Granny" in his memoir, "Dreams from My Father," and described meeting her during his 1988 trip to his father's homeland and their awkwardness as they struggled to communicate.