Beckham will be the captain of the Great Britain and Ireland side which squares off against Zinedine Zidane's Rest of the World XI at Old Trafford on November 14 in a charity match for UNICEF.
Ferguson will be the manager of the Great Britain side and Beckham had attempted to convince former Red Devils skipper Keane to also feature under the Scotsman.
However, a reunion between the two warring factions is not likely to take place as Beckham has now revealed that Keane is unavailable due to his commitments for the Republic of Ireland national team.
"We have asked Roy but obviously he is on international duty that is part of the problem with some of the other players we wanted to play," said Beckham.
"We have to pick a weekend where we felt we would get a lot of support and 3pm on Saturday does not happen very often. We have asked Roy but unfortunately he is tied up."