TAMPA, Fla. (WFLA) — The American Postal Workers Union rallied in Tampa on Thursday to speak out against a proposal by President Donald Trump to privatize the U.S. Postal Service.

Over 50 people turned up to protest outside the Carrollwood post office as part of a nationwide day of action. Organizers said over 150 communities across the country are holding demonstrations on Thursday.

Protesters held signs with messages like “Trump: hands off our public postal service” and “the post office belongs to the people, not the billionaires.”

This comes after Trump and billionaire Elon Musk proposed moving USPS into the commerce department or turning it into a private business. The USPS is also largely self-funded by charges for packages, stamps and other services, not by taxes.

“This is the people’s postal service, emphasis on ‘service,’” APWU President Mark Dimondstein said in a statement. “If this administration succeeds in taking over the USPS, it will lead to higher prices and reduced service, especially in rural areas.”

Tampa APWU President Don Barron said that if USPS is privatized, a single stamp could cost as much as $7.

“Privatizing the post office for the public will be a disaster,” Barron said. “They’re taking about raising the rates up to 140% and lowering the service for what is a national treasure, and it is something that the public needs to be aware is currently in process.”

The USPS, which has been operating for 205 years, is enshrined in the Constitution. It would take an act of Congress to change how the postal service operates.

“It belongs to the people on Main Street, it shouldn’t be handed over to Wall Street,” Dimondstein said. “The U.S. mail is not for sale.”