Rudy Giuliani on Tuesday resumed his public war with Mayor de Blasio — calling him “lazy,” and a “failure” and asserting that Hizzoner “broke my heart” by ending some of his crime-fighting policies.

Asked about the rise of anti-Semitic attacks in the city and upstate, including the brutal attack by a machete-wielding madman during a Hanukkah celebration in Rockland, Giuliani lambasted de Blasio for suggesting that President Trump bore some of the blame.

“He’s the mayor of the city of New York. He is in charge. And isn’t it fascinating that all of these communities that have been victimized by anti-Semitism …all of these communities, they love the president. They are his greatest supporters,” the former two-term mayor told guest host, Staten Island Councilman Joe Borelli, who was filling in for Joe Piscopo, on WOR AM radio’s “The Answer.”

“You’re the mayor, you’re responsible, do your job,” Giuliani said, before charging that de Blasio failed to learn lessons from the Holocaust.

“It’s hard to say in a nice way, [but] he’s probably the worst mayor in my lifetime. He’s a failure as a leader, he does exactly the opposite. You’re supposed to take responsibility as a leader, and he forgot, or maybe he never learned, the great lessons of the Holocaust,” he continued.

“The two great lessons of the Holocaust are: ‘Never forget, and ‘Never ignore.’ Never ignore means you have to stand up to the first act of anti-Semitism.

The former Gotham mayor, who is now Trump’s personal lawyer, said he would have tackled the problem at the first sign of rising anti-Semitism.

“Do you know how much it’s up this year? It’s up 29 percent, anti-Semitic acts. That is extraordinary. I started Compstat with [ex-police commissioner] Bill Bratton. If I had seen it up 2 percent, that’s when I wold have acted. Not at 10 percent, not at 15 percent, not at 20, and by the time you’re at 29, this is going to be very very hard to turn around, he declared, adding that the increase had nothing to do with the White house.

“That has nothing to do with Bill Clinton, he was president when I was president [sic] and it has nothing to do with Donald Trump. It has to do with you and the minute you think it doesn’t, you become a bad mayor, and he has become a very, very ineffective mayor in so many ways, but this is one that I think is inexcusable.”

Giuliani said that Trump’s support in the Orthodox community topped 90 percent, and that the president was staunchly pro-Israel before turning his attention back to the mayor.

“It’s either in you or it isn’t, and this man doesn’t even seem to, I don’t know, I think he’s lazy,” he said, adding that de Blasio was reversing many of his crime-fighting efforts and other policies, including welfare reform and Broken Windows policing.

“This man has broken my heart. He’s ruined things that I worked 24 hours a day, and my staff worked 24 hours a day, tremendous battles,” he said.

On Monday, de Blasio and Giuliani exchanged insults after Giuliani went after the mayor’s record on Twitter.

“It’s striking how out of touch Rudy Giuliani is at this point. He doesn’t even understand what’s happening in New York City,” de Blasio said in an interview.

“The NYPD very, very consistently deals with quality of life crimes, hate crimes, the smaller things like graffiti.”

Asked about the ex-mayor’s remarks, de Blasio spokeswoman Olivia Laperolerie said” “Rudy Giuliani should focus on his legal troubles instead of exploiting tragedies to sow division between New Yorkers.”

The US Attorney’s office in Manhattan is reportedly investigating Giuliani’s activities involving two Soviet-born former associated, lev Parnas and Igor Fruman.

The two-day verbal slugfest came a week after Jewish groups excoriated Giuliani for comments of his own, claiming in a New York Magazine interview that he was “more of a Jew” than Holocaust survivor and liberal financier George Soros.

“Don’t tell me I’m anti-Semitic if I oppose him,” he told the publication in one exchange.

“Soros is hardly a Jew. I’m more of a Jew than Soros is. I probably know more about — he doesn’t go to church, he doesn’t go to religion — synagogue. He doesn’t belong to a synagogue, he doesn’t support Israel, he’s an enemy of Israel. He’s elected eight anarchist DAs in the United States. He’s a horrible human being,” the former mayor said.

Jewish groups roundly denounced Giuliani’s statements as anti-Semitic.