Costs for President Donald Trump’s campaign rally in Minneapolis last month came in slightly higher than expected, and the city will continue to seek reimbursement, Mayor Jacob Frey said Tuesday.

After weeks of calculating the cost of police overtime, public works crews and road barriers, the city determined that it spent $542,733 — roughly $12,000 more than the original $530,000 cost estimate for the president’s rally at the 19,356-seat Target Center. The event drew national attention after Frey and Trump sparred over who should cover costs for the event, which drew large protests around the downtown arena.

The majority of the tab, some $392,139, was attributed to police costs, including overtime. Exactly how the city will seek reimbursement for those costs and whether it will succeed remains to be determined.

“We’re not taking any option off the table at this point,” Frey said.

The spending battle began before Trump took the stage at his event, widely seen as a milestone in the GOP effort to flip Minnesota in the 2020 presidential election. Republicans haven’t captured Minnesota in a presidential race since 1972, though in 2016 Trump lost by a margin of 1.5 percentage points, or less than 45,000 votes. As a result, both major political parties consider Minnesota a battleground state next year.

Frey said he would seek reimbursement from any candidate who held a similar event in the future.

“This is not an issue that is limited to one candidate or one party,” said Frey, a DFLer. “This is an overarching question that we need to look at in terms of the cost that cities are forced to bear.”

The city did not bear any costs for a smaller rally earlier this month for Democratic presidential candidate Bernie Sanders, whose campaign agreed to cover all expenses. That event was estimated to cost $40,275, with campus police at the University of Minnesota handling traffic and crowd control without seeking outside assistance from the city.

The city’s path to reimbursement for the Trump rally is unclear. The city did not have a direct contract with the Trump campaign. Instead, it contracts generally with AEG to manage the Target Center, and AEG contracted with the Trump campaign for the event.

The Trump campaign previously balked at requests to reimburse the city. On Tuesday, the campaign referred questions to the U.S. Secret Service, which could not immediately be reached.

As of Tuesday afternoon, the city had not sent a bill to AEG. Frey said the city continues to have discussions with AEG and did not eliminate the possibility that the city could sue at some point.

The mayor said he would like to work with council members to alter the city’s contract with AEG, possibly requiring analyses to ensure that the costs of future events could be offset by money brought in from event taxes.

“We can’t have our costs rising dramatically beyond what we receive in the form of sales and entertainment tax,” Frey said. He said he did not yet know how much money the city brought in from the sales and entertainment tax on Oct. 10, the day of the Trump rally.

Michael Roth, a spokesman for AEG, said he could not comment on Frey’s ideas for future contracts. But, Roth said in a statement, “We support Mayor Frey and agree that cities like the City of Minneapolis should not be responsible for costs incurred by the City related to campaign appearances.”