The campaign also warned that denying it the arena “would be viewed as a breach of contract and result in court action.” And the Trump law firm Jones Day wrote in a letter to the Target Center's management firm that the “last-minute squeeze” by the city government “seems to be nothing but a pretextual political effort with serious First Amendment ramifications.”

At the center of the burgeoning financial and political dispute is Frey, a 38-year-old former attorney and city councilman elected as mayor in 2017, who said last month that the president's “message of hatred will never be welcome in Minneapolis,” according to The Star Tribune.

Trump campaign manager Brad Parscale lashed out Monday night against the “radical Mayor of Minneapolis,” charging that Frey “is abusing his power in an attempt to block the President's supporters from seeing him speak“ at Thursday's rally.

“We refuse to be bullied by a left-winger resister & won't let him stifle the speech of @realDonaldTrump or his supporters!” he tweeted.

Parscale also wrote that Frey’s cost estimate represented “an outrageous abuse of power by a liberal mayor trying to deny the rights of his own city’s residents just because he hates the President!”

The radical Mayor of Minneapolis, @Jacob_Frey, is abusing his power in an attempt to block the President's supporters from seeing him speak on Thursday.

We refuse to be bullied by a left-winger resister & won't let him stifle the speech of @realDonaldTrump or his supporters! pic.twitter.com/ATnJNBRvFG

— Brad Parscale (@parscale) October 8, 2019

Trump joined in on the attacks Tuesday morning, retweeting Parscale and slamming both Frey and Rep. Ilhan Omar — one of his favorite Democratic foils in Congress, whose district includes Minneapolis.

“The lightweight mayor is hurting the great police and other wonderful supporters. 72,000 ticket requests already,” the president wrote. “Dump Frey and Omar! Make America Great Again!”

Frey responded an hour later, quoting Trump’s message and tweeting: “Yawn... Welcome to Minneapolis where we pay our bills, we govern with integrity, and we love all of our neighbors.”

But the president kept bludgeoning the mayor on social media, referencing a “Fox & Friends” segment on a newly introduced policy by the Minneapolis Police Department that bans officers from appearing in uniform in support of candidates at political events or in advertisements.

Lt. Bob Kroll, president of the Police Officers Federation of Minneapolis, had appeared on the morning cable news show earlier Tuesday to promote the union’s “Cops for Trump” T-shirts for officers to wear instead.

“The Police are fighting the Radical Left Mayor, and his ridiculous Uniform Ban. Actually, I LOVE the Cops for Trump shirts. Want to bring some home. I am with you 100%!!!!” the president tweeted.

“Someone please tell the Radical Left Mayor of Minneapolis that he can’t price out Free Speech. Probably illegal!” he added. “I stand strongly & proudly with the great Police Officers and Law Enforcement of Minneapolis and the Great State of Minnesota! See you Thursday Night!”

Frey retorted to that post, as well, tweeting: “Someone tell the President of the United States that he can afford to help pay for the extra time our officers will be putting in while he’s in town.”

Should the president's rally in Minneapolis proceed, it wouldn't be the first Trump campaign event to cause fiscal consternation among municipal officials. The campaign has yet to reimburse the city of El Paso, Texas, roughly a half-million dollars for the cost of a rally in February, and an investigation in June by the Center for Public Integrity found that at least nine other city governments are still waiting for Trump's campaign committee to pay public safety-related invoices associated with his rallies.