The Star said Guterres believes that Obasanjo is as much respected by Kenyan President Uhuru Kenyatta as by opposition leader Raila Odinga.
Obasanjo's mission is to persuade Odinga not to continue with his swearing-in ceremony, scheduled for January 20.
The former head of state of Nigeria arrived in Nairobi on Wednesday night, to try to reach an agreement between the candidates who opted for the presidency last August.
The day before, Obasanjo met with the principal directors of the opposition National Super Alliance (NASA) and tried to persuade them to abandon their plans.
Various press media claim that the UN recognizes the legitimacy of Kenyatta's government and is trying to prevent any outbreak of violence that results from that situation.
Obasanjo has a long relationship with Odinga, and is also a member of the High Level Advisory Board of the Secretary General of the United Nations on Mediation.
Obasanjo evolved as president of the Republic of Nigeria from 1999 to 2007, and before that as Head of the Federal Military Government of Nigeria and Commander in Chief of the Armed Forces of Nigeria of 1976 to 1979.
Throughout his political career, Obasanjo has participated in numerous international mediation efforts, including Angola, Burundi, Mozambique, Namibia and South Africa.
- Countries: Africa