Mayor de Blasio attacked the messenger Tuesday, whining about The Post’s hard-hitting coverage of First Lady Chirlane McCray’s embattled $1 billion mental health plan ThriveNYC.

“I would say that I don’t turn to the New York Post for facts,” de Blasio sniffed at an unrelated press conference in Queens Tuesday.

He made the remarks just a month after he credited The Post’s coverage of a trashed-out house in Queens with prodding his administration into action over the matter.

“The truth is that ThriveNYC is attempting to do what’s never been done before which is to create pervasive access to mental health services in New York City,” he argued, defending the program.

Critics across the political spectrum have questioned Thrive’s effectiveness since a vagrant bludgeoned four homeless men to death in Chinatown last weekend.

The attacker, Randy Santos, 24, left a fifth man in critical condition.

“We spend hundreds of millions of dollars on Thrive,” Democratic Councilwoman Carlina Rivera, who represents the Lower East Side, said on Sunday. “What are the metrics? What is the rubric we are using?” she asked.

City Comptroller Scott Stringer, another Democrat, said Monday, “Thrive must do better to ensure [its] programs are reaching those most in need of help.”

Staten Island Republican Councilman Joe Borelli added that the Chinatown attack highlights “the failure to address mental illness through ThriveNYC.”

De Blasio was asked by another reporter at the press conference Tuesday how he justified going on Fox News shows to tout his since-abandoned presidential campaign if the network is owned by The Post’s parent company, News Corp.

“They give you a chance to talk to their viewers in an open way that makes sense to take advantage of as with any other network. It’s very different than what happens on the print side,” he claimed.

The Post, he claimed, is “an ideological newspaper period and not given to the facts.”

When a third reporter compared Hizzoner’s attacks on The Post to President Trump’s denunciations of the media, de Blasio balked.

“The president attacks the media writ large in widely inappropriate terms,” de Blasio said.

“That’s very different than acknowledging a particular outlet has a consistent ideological bent and is willing to warp the facts in the name of their ideology,” he said.