Mayor Bill de Blasio blasted the NYPD’s top union on Monday night following the Police Benevolent Association’s call for a vote of “no confidence” against him and the police commissioner.

De Blasio said it was “reprehensible” that PBA President Patrick Lynch called for a public rebuke of hizzoner and Commissioner James O’Neill for firing cop Daniel Pantaleo.

“I think what the union is doing is reprehensible,” the mayor told Errol Louis on NY1’s “Inside City Hall.”

“The men and women of the NYPD know that Jimmy O’Neill cares about the city and cares about all the men and women who serve this city in our police department.”

The mayor and Louis were discussing the earlier firing of Pantaleo over the July 2014 chokehold death of Eric Garner — and the immediate fury the decision elicited from Lynch.

“We are asking for a no-confidence vote in the mayor and the police commissioner of this city of New York,” Lynch wrote in an email to members that noted the union’s executive board would put up a vote by all PBA delegates.

“It’s absolutely essential that the world know that the New York City Police Department is rudderless and frozen. The leadership has abandoned ship and left our police officers on the street alone, without backing,” the email continued.