The United States Postal Service, or USPS, filed a lawsuit against the city of Berkeley on Monday over a zoning ordinance that depletes the value of the Berkeley Main Post Office building and allegedly prevents its sale.

According to USPS spokesperson Augustine Ruiz, the Berkeley Main Post Office at 2000 Allston Way has been underutilized for several years. Because of the excess space and USPS’s “dire” financial concerns, the postal service decided to sell the building — which is located in the Civic Center Historic District — in 2012.

Ruiz said that because the building is no longer used for carrier service and instead only for retail, only 4,000 square feet of the 57,000-square-foot building are being used.

The Civic Center Historic District is part of the National Register of Historic Places and includes 12 buildings besides the post office. According to Councilmember Jesse Arreguin, several historic Berkeley buildings have been threatened by commercial interests, including the post office, the Veterans’ Memorial Building and Old City Hall.

Following USPS’s attempt to sell the building, Berkeley City Council passed a zoning ordinance in 2014 restricting use of buildings in the Civic Center Historic District of Berkeley for civic and nonprofit uses.

The U.S. Department of Justice wrote a letter to Mayor Tom Bates in April threatening to file a lawsuit, in which it stated that the zoning law “so drastically reduced the value of the property as to render a sale untenable.” In the same letter, the DOJ said the ordinance violated the Supremacy Clause of the US Constitution by defying the Constitution’s Postal Powers Clause and the Postal Reorganization Act, which gives USPS the power to provide and sell post offices as it determines is needed.

In a plan proposed by USPS during negotiations that spanned from December 2013 to November 2014, the postal service suggested a five-year lease of the space it actively uses from the new owner, followed by the option to extend that lease by up to 20 years. Under the plan, the city would also act as a covenant holder to oversee the preservation and maintenance of the building.

After the city and the post office disagreed about the amount the city should receive to hold this position and the term of the lease, however, the negotiations ended without resolution.

“I don’t feel that they are serious about trying to find a compromise to preserve the building. They want to sell the building, they’ve made that clear over the years,” Arreguin said. “We’re not gonna roll over, we’re not gonna let our historic postal service building be sold.”

Despite the conflict, Councilmember Kriss Worthington thinks that a compromise would be beneficial for the city and USPS.

“We should try to figure out if there’s a compromise possible and save the long and stressful process of a full-out lawsuit,” Worthington said.