The upcoming NATO and G-8 summits in Chicago could cost up to $65 million and require the help of out-of-state law enforcement officials to corral demonstrators and keep the peace, the summits’ organizers disclosed for the first time Thursday.

The price tag for back-to-back world summits, estimated by the G-8 and NATO Host Committee to be between $40 million and $65 million, would not be thrust upon Chicago taxpayers, officials said during a City Hall briefing. Rather, the money is expected to come from a combination of private sector fundraising and federal grants.

High-ranking officials from Mayor Rahm Emanuel’s administration also said Thursday that they’ve been in contact with law enforcement officials from other states, in case they’re needed to help with security at the overlapping world meetings, which will take place May 19-21. A mayoral proposal that would allow the Chicago Police Department to deputize out-of-state law enforcement is set to be considered by aldermen next week.

This spring’s dual summits will be the first time NATO and the G-8 have met in the same city in 35 years. City officials are bracing for hordes of protesters; they approved their first city protest permits Thursday.

But organizers say they’ve been working with federal security officials to prepare.

“Seattle is not Chicago,” said one top organizer, referring to the violent protests that broke out at the World Trade Organization meeting in Seattle in 1999. “Seattle was pre-9/11. Seattle was not prepared like Chicago is prepared.”

The meetings have been declared “national security special events,”  a designation the U.S. Department of Homeland Security usually gives to high-profile events such as the NFL Super Bowl and major political party nominating conventions, officials said. That designation means that the U.S. Secret Service will be in charge of security, and Chicago could be eligible for some federal funding to help pay for it.

Summit organizers and administration officials made their disclosures during a so-called “background briefing” organized by Emanuel’s press office. The officials spoke on the condition that they not have direct quotes attributed to them, in order to allow for a frank discussion with reporters, an Emanuel spokeswoman said.

Thursday’s wide-ranging briefing, which lasted for about 90 minutes, marks the first time Emanuel administration officials and organizers met with the press to talk at length about the upcoming meetings that are expected to draw about 10,000 people from 80 countries to Chicago in just four months’ time. It was attended by Lori Healey, Executive Director of the G-8 and NATO Host Committee who also worked on Chicago’s failed bid to win the 2016 Olympics; Felicia Davis, Mayor Rahm Emanuel’s First Deputy Chief of Staff; and Steve Patton, the City of Chicago’s top lawyer.

But the briefing left many questions unanswered.

Though a top summit organizer was adamant that the cost for the events would not be borne by taxpayers, the organizer declined to say how much private money had already been raised, how much they hoped to raise, or how much might come from the federal government. And while information on the private donors who give to the host committee will be posted online, some of that information will not be made public until after the summits are over, the organizer said.

Officials also could not say where law enforcement is planning to detain protesters who are arrested.

Emanuel administration officials did, however, use Thursday’s briefing to defend and clarify a proposed ordinance that would give the mayor more authority leading up to the NATO and G-8 summits. The measure would give the mayor’s office the power to circumvent normal city procedures, in some cases, in order to enter into contracts related to the summits; it would shorten the hours that city parks and beaches are open to the public; and it would allow the Chicago Police Department to deputize out-of-state law enforcement to help with security at the summits.

Administration officials softened some proposals

City Council Committees are scheduled to consider the ordinance Tuesday, with a possible vote Wednesday.