Bin Hammam drops latest leadership hint
The Asian Football Confederation president has not yet publicly announced whether he will stand for football's top job but kept the pressure on Blatter on Saturday while the FIFA president was in Wales for a meeting of the law-making International Board.
Bin Hammam posted a message on his Twitter and Facebook accounts, linked to his official website, that "competition is good for the organisation (FIFA), whether the president or any other posts."
He added that "competition is the best way to make the organisation vibrant and alive."
Blatter, 75 next week, has been president since succeeding Joao Havelange in 1998 and is up for re-election for a fourth four-year term.
The deadline to announce a challenge is March 31 and Bin Hammam could score a notable double by becoming FIFA president following Qatar's success in winning the right to stage the 2022 World Cup last year.
Bin Hammam told Reuters in January: "A change is a demand for an improvement really.
"I cannot be 100 percent frank with you but I think FIFA needs lot of improvement. I think there is a scope of work I can do, there is something I can present and do for international football."
One area of doubt for Bin Hammam is that a number of associations in his Asian confederation voted for Prince Ali of Jordan to become a FIFA vice-president in January, with Prince Ali believed to have Blatter's backing.
The countries that voted for Prince Ali have said they would support Blatter in any challenge to his leadership.