European and LaLiga champions Real Madrid won the latest Fifa Club World Cup tournament in February
Football's world governing body said on Tuesday the 2026 World Cup will feature 104 games, up from 64, and unveiled plans for a 32-team Club World Cup.
"Fifa continues its malpractice of making unilateral decisions on the world football calendar," said the La Liga statement, adding it will go to the World Leagues Forum (WLF) before taking the "appropriate next steps".
Representatives of players union Fifpro and the Professional Footballers Association have also criticised Fifa's plans, which were agreed on Tuesday at its council meeting in Rwanda.
The expanded 2026 World Cup, being held in the United States, Mexico and Canada, will see the number of participating nations increase from 32 to 48.
Fifa had proposed a format of 16 groups of three but has now opted for 12 groups of four, followed by a new last-32 round.
The move expands the competition from its projected 80 matches to 104 and also means teams will have to play eight games to win the tournament, compared to seven at the 2022 World Cup.
Fifa also approved the access list for the 32-team Club World Cup, which will take place every four years from June 2025.
The La Liga statement said: "Fifa is showing complete disregard for the importance of national championships, and the football community in general.
"Fifa completely neglects the economic damage these decisions inflict on leagues around the world. Leagues were not consulted about any of the changes presented.
"These decisions do not take into account the competitive, sporting and economic impact on national leagues, clubs and players, by further cramming an already overloaded schedule. Fifa only takes into account a small group of clubs and players."
La Liga said it would now analyse Fifa's plans with the WLF, an organisation representing professional association football leagues.
In December, the WLF criticised the announcement of a 32-team Club World Cup, saying it could have damaging consequences for the football economy and player welfare.
The European Leagues, which represents clubs across 34 European countries, said in a statement it is "concerned" about Fifa's plans, which it claims were created in a "unilateral way" without consultation with leagues.
"Unfortunately, this became a habit in the recent years," the statement said.
"Lately, governing bodies' solutions for football solely focus on adding new competitions and on further expanding existing competitions into an already heavily congested football calendar.
"This results in a privilege for a few clubs while completely disregarding the big negative economic and sporting impact these decisions have on domestic leagues, most of their clubs, players, and fans."
Player organisations and club managers have regularly voiced concerns about the demands on players, and Fifa is to set up a taskforce to look at player welfare and "principles such as mandatory rest periods".
-- Courtesy of BBC Sport