Advocates for allowing transgender women to compete in sports against biological women took a huge setback Sunday, at least in the world of elite swimming.

FINA, the sport’s world governing body, announced transgender women would not be allowed in major women’s races, effective Monday.FINA is known as the international swimming federation that’s recognized by the International Olympic Committee.

FINA stated it’s working to create an “open” category for some events for transgender who want to compete.The new policy didn’t absolutely disqualify transgender women from participating in women’s sports.