Asian Football Federation chief Bin Hammam, who is challenging incumbent Blatter for world soccer's top job in June's vote, was expected to travel to Miami [ Images ] to meet with the 35 CONCACAF delegates from North and Central America and the Caribbean.
But Bin Hammam wrote on his blog (http://www/afcpresident.com/en/Blog/) "I had hoped to be present to share my plans for the future in Miami but unfortunately I will not be able to attend due to issues beyond my control".
While Bin Hammam said he hoped to meet with member associations from the region in the coming weeks it will be a blow to his campaign to miss out on the chance to speak directly to delegates.
The website Inside World Football cited unnamed sources as informing them that Bin Hammam was not able to receive a US visa to travel to Miami. CONCACAF were not immediately available to comment on the report.
The CONCACAF Congress will re-elect Trinidadian Jack Warner as president unopposed in a vote -- Warner has long been viewed as a key Blatter ally.
CONCACAF tends to vote as a block in FIFA elections and general secretary, Chuck Blazer of the United States recently said he hoped they would do so again.
"We make a collective decision in our congress so as to have a greater impact on the results," he told Reuters in March.
Qatari Bin Hammam was in South America during the weekend where he spoke at the CONMEBOL Congress and said FIFA needed "new blood".
The 75-year-old Blatter is running for a fourth term having taken over as FIFA boss in 1998.