Water bottles have been banned by airport security for years but now some are suggesting that theme parks may be following suit by prohibiting outside liquids too.

On Monday, guests at Universal Studios Orlando were greeted to an announcement upon arrival that they were not allowed to bring bottled water, or other outside liquids, into any of the theme parks or the CityWalk area, reports the Orlando Sentinel.

The park has not clarified why the new policy was enacted, but Tom Schroder, a Universal Studios spokesman, said via email that "This is the result of a review of our procedures and is not permanent." According to the Sentinel, Schroder did not indicate the length of the ban or elaborate on details.

Visitors were told they may bring in baby formula or necessary medicines.

Previously, the park has prohibited guests from bringing in their own lunches but has permitted small snacks and bottled beverages.

Some online have speculated that the temporary ban could be a park measure to prevent guests from bringing in alcohol during its Mardi Gras special event, which began earlier this Feb. and runs through mid April. But hospitality professor Scott Smith says the ban could be a security measure similar to those enacted by TSA.

"It might be that they're concerned about security, but in the end they're going to end up selling more food and beverages through not allowing people to bring in the liquid," Smith told the newspaper.

Regardless of the reason, many visitors to the park were not pleased after being forced to give up their liquids at the park entrance.

Visitor Mark Mantel remarked that lines getting into the parks were slower as patrons were confused by the new policy. Many brought in empty containers after dumping the liquids.

"I just couldn't believe it," Mantel said. "I just was thrown off."

FoxNews.com reached out to Universal Orlando and is awaiting comment.