They’re all screaming for no ice cream.

Overprotective Park Slope parents have declared war on a treasured rite of spring: an ice cream in the park.

The icy rebuke of the time-honored tradition erupted on the Park Slope Parents online group when one mother described her son’s meltdown in Prospect Park after she put the ixnay on a acksnay.

“Along with the first truly beautiful day of the year, my son and I had our first ruined day at the playground,” the poster named Sarah somberly recounted. “Two different people came into the actual playground with ice cream/Italian ice push carts. I was able to avoid it for a little while but eventually I left with a crying 4-year-old.”

Another angry mother, identified on the site as Dorothy Scanlan, chimed in.

“I should not have to fight with my children every warm day on the playground just so someone can make a living!” the poster wailed. “I too was at the 9th Street Playground on Monday, and one of the vendors just handed my 4-year-old an ice cream cone. I was furious.”

But not all parents in brownstone Brooklyn’s politically correct bastion are so hot and bothered.

“I think they’re crazy,” laughed Lynette Barenboyn, a stay-at-home mom. “In Park Slope, everybody has an opinion, and there are a lot of opinions — especially when it comes to parenting.”

One mom — who asked to remain anonymous for fear of being ostracized by other parents — said her friends want an ice-cream ban, but she disagrees.

“People just need to say no,” the mom said while with her son at Prospect Park’s aptly named Harmony Playground. “I say no to him all the time, and I feel his wrath. But he needs to hear that no.”

The mom, who also pointed out that she doesn’t feed her children kale chips, described the typical Park Slope parent as “militant.”

Dixie Kissoon, a nanny who also took her charges to Harmony recently, wishes the worked-up moms and dads would just get a life.

“They’re obnoxious,” she said. “There’s no harm in this.”

But Sarah Schenck says just say no to frozen confections.

Schenck, a mother of two and co-founder of the eco-friendly parentearth.com, said statistics back her up.

“Nobody wants to be a crank, but one in three kids are going to be obese or diabetic by high school,” she said. “When my kids see other kids get ice cream, they just start begging me. I just don’t think these are the fights we should be having.”

Kenny Sonders, another parent at the playground, said he thinks these are exactly the fights parents should be having. “It’s part of growing up in Brooklyn.”