New York City Mayor Bill de Blasio’s strut into the 2020 Democratic primary is getting rebuffed by the city’s biggest police union which warned American voters that he would be an “unmitigated disaster” in the White House.

Patrick J. Lynch, president of the Police Benevolent Association of the City of New York, issued a statement on Twitter calling de Blasio’s bid “laughable.” Relations between the mayor and the union and police have been sour for some time.