Honolulu is prepping for a national gathering of mayors. But who’s footing the bill?

For the first time since 1963, the nation's mayors will head to Hawaii for an annual conference

HONOLULU, Hawaii (HawaiiNewsNow) - The U.S. Conference of Mayors will be held on Oahu later this month. It’s expected to cost the city about $5 million to put on.

But taxpayers aren’t the only ones paying for it. As good as that sounds, it’s raising some red flags to some who worry about conflicts of interest.

The Caldwell Administration said it has raised more than $3.3 million from private donors to pay for the conference in Waikiki at the end of June.

Much of that money came from city contractors and subcontractors or from companies like AirBNB and Uber who are fighting hard against City Council measures to regulate their businesses.

“I think there are some concerns" said Colin Moore, University of Hawaii political science professor. “Sponsors who do business with the city or are involved in rail projects ... you have to wonder what they’re getting as a result of the sponsorship.”

The city said the sponsorships pose no ethical problems.

“The City and County of Honolulu has proper protocols and procedures in place to ensure such support does not create conflicts of interest," said city spokesman Andrew Pereira.

According to the conference website, donors include the engineering firm AECOM, which contributed at least $150,000 and Kiewit Pacific and Stantec , which contributed more than $25,000 to the event.

All three companies work as contractors or subs for the controversial Honolulu rail project.

Other big donors include AirBNB, Expedia, Lyft and Uber. These companies have long opposed city efforts to regulate their industries.

“One would have to look very carefully to see if these donations are being made to influence the city in future policies," said Ian Lind, investigative reporter and former Common Cause director.

The conference will be held at the Hilton Hawaiian Village from June 28 to July 1.

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