The world soccer players' union filed a legal claim against FIFA for expanding the Club World Cup, FIFPRO said on Thursday.

The 32-team event, up from seven teams, is slated for June-July 2025 in the United States. It is traditionally staged in December.

FIFPRO is concerned about the physical and mental demands on players.

It said unions in England and France filed a claim at the Brussels Court of Commerce, which also challenged FIFA’s “decisions to unilaterally set the international match calendar,” determining the schedule for international games and competitions.

FIFPRO said unions believe decisions like the expanded Club World Cup “violate the rights of players and their unions.”

The Brussels court is being asked to refer the case to the European Court of Justice.

“Players and their unions have consistently highlighted the current football calendar as overloaded and unworkable,” FIFPRO Europe said in a statement.

FIFA revealed details of its expanded Club World Cup in December. FIFPRO quickly opposed the plans, which it said showed a "lack of consideration for the mental and physical health of participating players, as well as a disregard for their personal and family lives.”

FIFA said the timing of the month-long tournament, during the offseason for many major leagues around the world, would ensure sufficient rest for players.

That assertion is disputed.

“Once preparation periods and travel are included, the tournament is likely to create up to six weeks of additional work to be added to an already crowded schedule,” it said. “The role of FIFPRO Europe and its members is not to favor or oppose one competition over another. However, in the wider context of the global football calendar, the new FIFA Club World Cup is seen by players and unions as representing a tipping point.”

FIFA says the international match calendar is published after consultation with the relevant stakeholders.

Staging the Club World Cup in 2025 means top players face three straight years of major competitions during the usual offseason, given the European Championship and Copa America are being staged this year and the next World Cup is in 2026.

“Since all attempts at dialogue have failed, it is now up to us to ensure that the fundamental rights of players are fully respected by taking the matter to the European courts and thus to the ECJ," FIFPRO Europe president David Terrier said. "It’s not a question of stigmatising a particular competition, but of denouncing both the underlying problem and the straw that broke the camel’s back.”

Despite the opposition of FIFPRO, the European Clubs Association has said the Club World Cup was “fantastic news for club football in general.”

The Associated Press contact FIFA for comment.