Stella Obasanjo (search), the wife of Nigeria's president, died Sunday in Spain. She was 59.

Stella Obasanjo, described as President Olusegun Obasanjo's (search) "beloved wife," died after undergoing surgery, according to a brief statement signed by presidential spokeswoman Remi Oyo. No further details were given.

The Spanish Foreign Ministry (search) said Obasanjo's wife died Sunday morning at a hospital in the southern Spanish resort city of Marbella, where she had been on a private visit.

The ministry said it had no information on the cause of death and did not know if she had undergone surgery, as asserted by Nigerian officials in Abuja.

The body was taken to a coroner's office in nearby Malaga for an autopsy, the ministry said.

Obasanjo is president of Sub-Saharan Africa's most-populous nation of 130 million people and has played a key role as peace mediator in West Africa.

Kenya's President Mwai Kibaki sent a message of condolence to Obasanjo and described the leader's wife as a motherly figure who inspired women in Nigeria and across Africa.

"On behalf of the government and the people of Kenya, and on my own behalf, I extend our heartfelt condolences to your presidency personally and through you to all Nigerians," Kibaki said in a statement.

She is survived by her husband and a child.