President Donald Trump ripped Minneapolis Mayor Jacob Frey as a “lightweight” for trying to block his rally scheduled for Thursday from taking place.

“The lightweight mayor is hurting the great police and other wonderful supporters,” Trump wrote on Twitter. “72,000 ticket requests already. Dump Frey and Omar!”

The lightweight mayor is hurting the great police and other wonderful supporters. 72,000 ticket requests already. Dump Frey and Omar! Make America Great Again! https://t.co/ibTqvSbsbn — Donald J. Trump (@realDonaldTrump) October 8, 2019

The Trump campaign revealed Monday night that Frey was trying to tack on a $530,000 security fee and other costs to the management of the Target Center for the scheduled rally, prompting management to pass on the fees to the campaign.

“This is 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,” Trump campaign manager Brad Parscale said in a statement sent to reporters.

In response, the Trump campaign threatened to sue the Target Center for a breach in contract.

“This last-minute squeeze seems to be nothing but a pretextual political effort with serious First Amendment ramifications,” a letter read from the Trump campaign’s lawyer to the Target Center’s management firm.

In 2009, President Barack Obama rallied at the Target Center, which led to an estimated $20,000 cost for additional security from the police chief, according to a report at the time.

In September, Frey said that Trump was not welcome in his city.

“While there is no legal mechanism to prevent the president from visiting, his message of hatred will never be welcome in Minneapolis,” he said in September.

The Minneapolis police chief also enacted a new policy banning the department’s police officers from attending the rally in uniform.