Soccer-Blatter says he tried to act as intermediary in Burundi crisis
"I proposed to the president, who is a big football fan, in front of witnesses that, if it could be an advantage for him or his country, FIFA could deploy him as a ambassador for football in Africa, or the world," Blatter was quoted as saying in "Sepp Blatter: Mission and Passion Football" by Swiss journalist Thomas Renggli.
"Unfortunately, it didn`t work out," Blatter said.
Nkurunziza was re-elected for a third term in July in an election boycotted by the opposition. More than 400 people have been killed in the unrest and tit-for-tat killings continue.
The book said that the attempted negotiation happened around "one year ago".
During his years at the head of FIFA, Blatter assumed a quasi-diplomatic role, rubbing shoulders heads of state from all over the world and portraying soccer as a tool for peace.
The Swiss foreign ministry (FDFA) said in a statement that there had been contact between Blatter and State Secretary Yves Rossier, but denied the ministry had asked Nkurunziza not to run for another term.