In a sudden policy shift, football's governing body FIFA has prohibited spectators from carrying reusable water bottles into World Cup venues, leaving fans with no choice but to purchase beverages on-site, according to a Wednesday report by The Athletic.
Last month, the tournament's official stadium code of conduct allowed spectators to bring in empty, clear plastic bottles of up to one liter.
However, those guidelines have now been changed to completely ban refillable bottles.
"For the avoidance of doubt, reusable water bottles may not be brought into the stadium," the updated stadium code of conduct read.
In a statement to AFP, a FIFA spokesperson said the rule change was taken on safety grounds, noting that several World Cup venues already bar the use of refillable water bottles.
"FIFA is committed to protecting the health and safety of all players, referees, fans, volunteers, and staff," the statement read. "FIFA made the decision to prohibit bottles to prevent risk and injury to players and attendees."
The statement further said that outside bottles were already "prohibited at several of these venues for safety considerations" and that FIFA decided to apply this rule "across its tournament stadiums."
The statement added that misting stations, fans, hydration stations, and cooling tents would be available in "the stadium footprint."
It also said that bottled water inside the venue would be sold at prices that are "consistent with other events held at each stadium."
The rule change came despite experts warning fans could face health risks from extreme heat at open-air venues during the World Cup, which is being co-hosted by the United States, Canada and Mexico.
A report published by the World Weather Attribution research group last month estimated that 26 of the 104 games at the World Cup are likely to be played in conditions where the Wet Bulb Global Temperature (WBGT) exceeds 26 degrees Celsius.
WBGT is a measure of heat stress on the human body, which combines temperature, humidity, wind, and sunlight.
Supporters were barred from bringing water bottles into venues at last year's FIFA Club World Cup in the United States, where fans complained of searing temperatures.