The U.S. Department of Homeland Security says it will not comply with a new Denver ordinance that bans law enforcement, including federal agents, from wearing face coverings while operating in the city limits.

The ordinance, passed unanimously on Monday by the Denver City Council, says all law enforcement personnel must have their badge or identification number displayed and bans the use of a “facial covering when performing duties.”

The ordinance makes exemptions for special weapons and tactics, tactical operations and undercover work.

According to DHS, federal agents wear face coverings to protect from being doxxed by activists. The department says the city’s ban and others like it are unconstitutional because of the Supremacy Clause.

“Sanctuary politicians attempting to ban our federal law enforcement from wearing masks is despicable and a flagrant attempt to endanger our officers. To be crystal clear: We will not abide by unconstitutional bans,” DHS Deputy Assistant Secretary Lauren Bis told The Center Square on Tuesday, answering a question by email. “The Supremacy Clause makes it clear that state politicians do not control federal law enforcement.”

A federal judge last month blocked a California law that sought to ban U.S. Immigration and Customs Enforcement agents from wearing masks.

Mayor Mike Johnston’s office told The Center Square in an email that Denver’s ordinance is different in that it applies to local, state and federal law enforcement “rather than being tailored toward the federal government.”

The Denver Police Department is working with the city attorney and council members “to determine what implementation could look like” for the ordinance, a police spokesperson told The Center Square.

“Of utmost importance is discretion and prioritizing de-escalation when encountering these situations,” the spokesperson said in an email. “Our goal is to apply this ordinance in a way that builds trust and transparency without putting officers, deputies or the public at risk.”

Johnston plans on signing the ordinance this week, his office said. The ordinance’s final passage comes after the mayor last week signed an executive order that bars federal immigration authorities from using city properties in staging for civil immigration enforcement operations.Bies added that federal law enforcement officers have seen an increase in assaults against them.“The men and women at CBP, ICE and all of our federal law enforcement agencies put their lives on the line every day to arrest violent criminal illegal aliens to protect and defend the lives of American citizens,” the Homeland Security official said. “Make no mistake, this type of demonization is contributing to the surge in assaults of law enforcement officers.”