MILWAUKEE (CBS 58) -- A week of elevated tension between the Milwaukee police union and the city could come to ahead Friday morning when the union protests near an event the mayor is hosting.

It comes as the years-long battle over a police contract intensifies as the two sides near arbitration.

The mayor will be at City Hall for an event at 9 am. The police union will head that way at 10 am.

Negotiations have not gone well in recent weeks, with little communication between the two sides.

And no surprise, the bitter divide comes down to money.

A letter from the police supervisors' union to its members outlines the final offers for the contract that would be in effect for 2023-2025.

The union proposes two 2.25% raises in each of the first two years, then a 3.75% raise for all of 2025.

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