There’s bad blood between them.

Former President Donald Trump lashed out at pop star Taylor Swift Sunday, declaring his disdain — days after she endorsed Vice President Kamala Harris.

“I HATE TAYLOR SWIFT!” Trump, 78, wrote on Truth Social in all caps, without elaborating further.

Swift, 34, posted her endorsement of Harris just after the high-stakes ABC News debate between Trump and Harris last Tuesday. She previously backed President Biden in the 2020 election.

“I’m voting for @kamalaharris because she fights for the rights and causes I believe need a warrior to champion them,” the billionaire singer wrote on Instagram to her 284 million followers minutes after the debate wrapped up.

“She is a steady-handed, gifted leader and I believe we can accomplish so much more in this country if we are led by calm and not chaos.”

She added: “If you haven’t already, now is a great time to do your research on the issues at hand and the stances these candidates take on the topics that matter to you the most.”

She also took a shot at GOP vice presidential nominee JD Vance, signing her post “Childless Cat Lady,” in a jab at his 2021 interview with Tucker Carlson.

The photo she used in the post featured her posing with her Ragdoll cat Benjamin Button.

Tim Walz, Harris’ running mate, heaped praise on Swift following her endorsement.

“Here’s my life hack for all the guys out there: surround yourself with smart women and listen to them and you’ll do just fine. That includes my fellow cat owner Taylor Swift,” the Minnesota governor.

“It’s really great to have all of these women help us beat the smallest man in the world.”

Allies of Trump swiftly erupted against the pop icon. Questions had just begun to swirl whether Swift would endorse the Democratic nominee in the 2024 election cycle — as she did in Biden in 2020.

Trump, himself, has previously badmouthed the influential singer following the endorsement.

Kansas City Chiefs quarterback Patrick Mahomes’s wife, Brittany liked a post from Trump about the 2024 GOP platform, which drew backlash from fans last month. Swift is dating Kansas City Chiefs tight end Travis Lelce.

“Well, I actually like Mrs. Mahomes much better,” Trump sniped on Fox News after the debate. “It was just a question of time. You couldn’t possibly endorse Biden. But she’s a very liberal person, she seems to always endorse a Democrat — and she’ll probably pay a price for it in the marketplace.”

In the social media endorsement of Harris, Taylor Swift called herself a “childless cat lady.”
In the social media endorsement of Harris, Taylor Swift called herself a “childless cat lady.”Taylor Swift / Instagram

The former president, who has a proclivity for raging against celebrities who snub him, had stressed that “I was not a Taylor Swift fan.”

The “Cruel Summer” singer had once eschewed politics, before wading into the 2018 Tennesee Senate race in which she backed former Gov. Phil Bredesen (D) against then-congresswoman Republican Marsha Blackburn, who ultimately won.

Within 24 hours after Swift posted the endorsement, over 400,000 users clicked on an accompanied link in her Instagram story to Vote.gov, per a spokesperson for the General Services Administration which helps run the website.

Swift had urged her fans to register to vote in the upcoming Nov. 5 presidential election.

Despite her fame and influence particularly among younger voters, the 34-year-old’s endorsement appears to have done little to alter the 2024 landscape.

Only 6% of voters indicated that Swift’s endorsement makes them more likely to back her in the election with 13% saying it makes them less likely and 81% revealing it would make no difference, per an ABC News/Ipsos poll. 

Another post-debate poll from YouGov concluded that 8% of voters felt her stamp approval makes them “somewhat” or “much more likely” to vote for Harris, compared to 20% who indicated it makes them “somewhat” or “much less likely” to back her. A majority of those sampled, 66%, said Swift’s endorsement said it would have no impact.