Swiss Blatter, who turned 77 this month, was elected president of football's world governing body in 1998 and has consistently refused to rule out standing again in two years as long as his health permits.
"I will not carry on as long as there is at least one candidate prepared to continue my work," Blatter said in an interview with Spanish sports daily AS published on Thursday.
"The most important thing for me is that the person who takes over FIFA does so with the spirit of globalisation of football that we have developed in recent years," he added.
Blatter named two possible successors: former France international Michel Platini, who is the president of European governing body UEFA, and Angel Maria Villar, the president of the Spanish soccer federation (RFEF) and a vice president of both UEFA and FIFA.
"Michel Platini could be a possible successor as we started together in 1998," Blatter said.
"On the other side is Angel Villar who has had a long career and has good contacts in America and Africa and who would also be a good candidate.
"I don't know if there is a deal between Villar and Platini on these UEFA and FIFA issues but in any case the elections for the FIFA presidency in 2015 will be open and democratic."