FIFA's proposals are set to be voted on in December by the 211 member associations of global soccer's governing body, with president Gianni Infantino travelling the world to rally support for the plan, which has been fronted by former Arsenal manager Arsene Wenger.

While sources close to FIFA indicate that Infantino is confident he can get a majority, with support from federations in Africa, Asia and the Caribbean, turning that support into actual change may prove more difficult.

European and South American clubs, leagues and confederations are confident they can stop the plan, regardless of the outcome of a vote, multiple sources have told Reuters, raising the prospect of a damaging split in the international game.

Danish federation chairman Jesper Moeller, whose association was one of six representing Nordic countries to criticise the plan on Friday, went as far as to warn publicly: "In the worst case and last resort, it can not be ruled out that it could lead to federations opting out of FIFA in protest and lack of desire for the new set-up."

FIFA has argued that a biennial World Cup would lead to increased chances for countries to play in the tournament and that a streamlined qualification process, with fewer international breaks, would reduce international travel for players.

However, European confederation UEFA says that a more frequently held World Cup would dilute the competition's prestige and that holding major tournaments every year would increase the load on players and crowd the schedule.

In a statement to Reuters on Friday, UEFA said that the proposals "would damage all forms of football and devalue the competition itself".

"This concept has all the hallmarks of a decision that FIFA wants to take in haste and leave the rest of the game to repent bitterly at leisure. Any perceived attraction is shallow, while the pitfalls are cavernous," the organisation said.

"UEFA will continue to oppose it until common sense prevails and the plans are dropped."

South American body CONMEBOL is also opposed to the plans.

"Considering the clubs, the leagues, UEFA and CONMEBOL are all against this, it is unlikely that they would abide by the FIFA calendar," said one senior football industry source with knowledge of the discussions between opponents of the plan.

Underlining European opposition the Nordic football associations combined Friday to criticise the proposals.

The federations from Denmark, Sweden, Norway, Finland, Iceland and the Faroes said the proposals would harm European, other continental and women's football, and add to the player workload.

Moeller said the FIFA plans would destroy all efforts to promote women's football which has a strong standing in the region.

Infantino shows no sign of backing down, however, and was holding meetings with South American federations on Friday.

FIFA's ruling council is due to meet on Wednesday when it is expected to decide whether December's meeting of all their federations will be a full Extraordinary Congress or another 'global summit'.

The proposals are part of a major overhaul of the international match calendar, which determines when clubs have to release players for international duty.

The legitimacy of that calendar would be challenged if a biennial World Cup were to be included and then boycotted.

In practice, that would mean that while FIFA created windows for qualification matches for the additional World Cup, Europeans and South Americans would not participate in those games and would therefore be operating de facto with a separate calendar.

Sources have told Reuters that the various organisations representing clubs, leagues and other representative bodies have been coordinating closely with Uefa on how to respond to the vote in December.

"For once, they are all on the same page," said one European football administrator.

The European Club Association (ECA), which represents 234 top European teams, believes that FIFA's approach has been in "direct and unilateral breach of certain legal obligations," according to a statement last month.

The ECA has a Memorandum of Understanding with FIFA regarding the match calendar and how it should be formulated.

Australian Associated Press