Stephen Mandel won't give any details, saying councillors need to hear about and discuss the issues at the meeting Wednesday afternoon.
Councillors don't know what exactly the arena update will be, but Don Iveson thinks it must be something of substance.
Last week, Mandel asked for and got the support of the Capital Region Board to support Edmonton's bid for a $25 million portion of the Regional Collaboration Program.
The program is expected to offer $141 million over the next three years for projects that benefit regions as a whole.
If the application is successful, and the city receives the full amount, Edmonton would still need to find $30 million to cover the remaining amount for the arena.
City council voted unanimously last week to defer the debate on funding for the downtown arena to a later date, to give time to explore other funding options for the project.
The city has already agreed in principle to build a rink and share the costs with Edmonton Oilers owner Daryl Katz.
The Katz Group wouldn't confirm if they'd have someone at Wednesday's meeting, but officials seemed encouraged by the mayor's optimism.
The arena has divided citizens and detractors say the deal is too lopsided in favour of Katz if public money is needed for the rink.
Edmonton taxpayers will pay $219 million toward the 18,559-seat facility, which has a futuristic design of metal and glass.
The Oilers' share will be $143 million. Another $125 million will come from a ticket tax that wouldn't exceed seven per cent of the total cost of a ducat.
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