Fifa presidential candidate Prince Ali bin Al Hussein has accused a key rival of being a part of a "blatant attempt to engineer a bloc vote" and has called on the organisation to investigate.
The Jordanian Prince has suggested rival Sheikh Salman bin Ibrahim al Khalifa may have breached electoral rules after a cooperation agreement was signed between the Asian football federation - which is headed by Bahrain's Sheikh Salman - and its African counterpart.
Fifa's 209 football associations will elect Sepp Blatter's replacement as Fifa president on 26 February - with 100 votes coming from within the African and Asian confederations.
The Confederation of African Football (Caf) and the Asian Football Confederation (AFC) signed a Memorandum of Understanding to "strengthen and intensify cooperation and strengthen the capacity of various stakeholders in Africa and Asia" on Friday.
Read more: Who is Prince Ali Bin Al-Hussein?
In a statement, Prince Ali said: "I am concerned that there has been an attempt to breach electoral rules in the FIFA Presidential election. I have written to the Fifa Ad Hoc Electoral Committee informing them of my concerns and asking them to examine the matter.
"I have always promoted cross-regional understanding, however the timing of this Memorandum of Understanding looks like a blatant attempt to engineer a bloc vote.
"Questions must be asked: was this deal approved by the members of the executive committees of both the AFC and Caf and is the timing of the announcement, prior to a presidential election, acceptable?"
Prince Ali stood against Blatter in Fifa's last election in May but was comfortably beaten by the Swiss.
However, Blatter - now banned for eight years - stood down soon after, paving the way for a new election.