Mayor Bill de Blasio issued a fiery challenge to President Donald Trump and Attorney General Jeff Sessions on Friday night, demanding they come to New York City and tell police officers to their faces that they city was — as the Justice Department alleged — "soft on crime."

The Trump administration sent a letter Friday morning to a number of major cities, all of which have limited law enforcement cooperation with federal authorities over local residents' immigration status. The letter threatened to cut off the cities' law enforcement grants over their sanctuary city status.

In a statement accompanying the letters, the Justice Department specifically called out what it called New York City's "soft on crime" stance as causing an increase in murders.

That had de Blasio and NYPD Commissioner James O'Neill fuming.

"I'm telling you right now it's an unacceptable statement that denigrates the people of New York City and the men and women of the NYPD," de Blasio said. "This is an insult, this statement."

O'Neill added that his "blood began to boil" when he read it.

De Blasio demanded that Trump and Sessions either renounce the statement or stand behind it.

"I would say to President Trump and to Attorney General Sessions, if you believe this statement is accurate, come here to New York City, look our police officers in the eye and tell them you believe they are soft on crime. See how that feels," the mayor said.

The Justice Department responded Friday night, saying "it is New York City's policies that are soft on crime."

The department said the de Blasio administration is responsible for policies that led to "a dangerous MS-13 gang member walking out of Rikers Island in February" and that "endanger the lives of the hard working men and women of the NYPD."

In a statement, the NYPD Sergeants Benevolent Association, a police union, said the Justice Department was "absolutely correct" and that City Hall has "placed in jeopardy millions in U.S. Department of Justice grant funds that we count on to help protect our communities."