The pressure for Republican mayoral nominee Curtis Sliwa to drop out of the race is reaching a fever pitch with two weeks left until the election — as even his boss at WABC radio is now calling on him to ditch his long-shot bid.

Big Apple GOP bigwig John Catsimatidis urged the red-bereted Guardian Angels founder to end his floundering mayoral campaign in a bid to consolidate the vote behind ex-Gov. Andrew Cuomo and beat far-left Democratic front-runner Zohran Mamdani.0

“Curtis would make the best mayor of all the candidates … but Curtis has to realize that he should love New York more than anything else,” Catsimatidis told Sid Rosenberg on WABC radio Monday. 

The billionaire businessman had been calling for the field of mayoral contenders to narrow since the summer, but previously stopped short of telling Sliwa to bow out — telling The Post repeatedly he didn’t want to do that to a friend.

Sliwa, the colorful 71-year-old conservative candidate, activist and infamous cat lover, has been squeezed by influential GOP members and the city’s donor class to follow in the footsteps of Mayor Eric Adams, who ditched his unlikely re-election bid late last month.

Those amping up the pressure argue a two-man race would boost independent hopeful Cuomo’s chances of beating socialist Mamdani, the Dem Party’s nominee, on November 4.

Sliwa has repeatedly shrugged off the calls to drop out, even claiming he’d turned down $10 million in “bribes” — but Monday marked the first time his longtime friend, and more importantly boss, pushed for him to hang up his beret.

“He could win the next election because people will be proud of him for doing the right thing for New York City, instead of the wrong thing,” Catsimatidis told Rosenberg on “Sid and Friends in the Morning.”

“We cannot take a chance on Zohran [Mamdani] winning and every common-sense New Yorker feels the same way,” he said.

“I think Curtis would be a hero if we beat Zohran.”

The magnate boss of Manhattan’s Gristedes and D’Agostino Supermarkets chains also owns WABC, where Sliwa has his day job as a radio personality, though he’s currently on leave while campaigning. 

The shocking comments came just weeks after Catsimatidis publicly said he wouldn’t cross his pal and employee — despite running a shadow campaign to stave off a Mamdani mayoralty at any cost. 

Rosenberg also chimed in during Monday morning’s show, noting why the two were calling on Sliwa to drop out now.

“We didn’t do this a month or two months ago, but his poll numbers aren’t going up,” he said.

Rosenberg noted that a Cuomo victory wasn’t guaranteed even with Sliwa out, but said that it would give the ex-governor a better shot.

Sliwa still wasn’t hearing it.

“Curtis is not dropping out; this news does not impact him whatsoever,” campaign spokesperson Daniel Kurzya said.

“They’re entitled to their opinions, but there are 15 days to go, and the people will decide who the next mayor is,” Kurzya said, adding that Cuomo “should go out and get his own votes.”

Sliwa still has the backing of the five GOP county chairs, as well as the support of influential New York Republican Reps. Elise Stefanik and Mike Lawler. 

But the party’s leader, President Trump, has repeatedly tried to get Sliwa to ditch his bid, both publicly and behind the scenes since at least the summer, working to shape the mayoral race into a one-on-one contest.

“I don’t know. Is he a Republican? I don’t know,” Trump said of Sliwa on Fox News’ “Sunday Morning Futures.”

“This isn’t exactly ideal with where he wants to make Gracie mansion a home for the cats, you know?”

Even if Sliwa bowed out, Cuomo still has a sizable amount of ground to make up.