Blatter is not standing, having been banned for eight years for ethics violations.
“Four of the five candidates have spoken to me. I cannot take sides, that is not possible,” Blatter told French radio RMC.
He said several national federations had asked him who they should vote for, but he told them to vote as they saw fit.
Bahraini Royal Sheikh Salman bin Ebrahim Al Khalifa and UEFA general secretary Gianni Infantino of Switzerland are the two front-runners.
The other candidates are Jordan’s Prince Ali bin Al Hussein, Frenchman Jerome Champagne, the former deputy general secretary of FIFA, and South African businessman and politician Tokyo Sexwale.
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