CHICAGO (CBS SF/AP) — The wife of “Star Wars” creator George Lucas said Tuesday that opposition to a Chicago lakefront museum by a parks advocacy group has prompted a search outside the city for a site.

Friends of the Parks sued last year to stop plans to build the art museum near Soldier Field on a site that is now a parking lot. The nonprofit group says the plans violated laws restricting development along Lake Michigan. And in a statement Tuesday, the parks group indicated it would be opposed to an alternate site nearby.

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Lucas’ wife, financial executive Mellody Hobson, expressed frustration at the organization’s opposition, saying she and Lucas worked for two years to finalize “what would be the largest philanthropic gift to an American city in the 21st century.”

“We are now seriously pursuing locations outside of Chicago,” Hobson said in a statement. “If the museum is forced to leave, it will be because of the Friends of the Parks and that is no victory for anyone…. In refusing to accept the extraordinary public benefits of the museum, the Friends of the Parks has proven itself to be no friend of Chicago.”

The latest proposal the parks group opposes calls for demolition of part of McCormick Place, which is also by the lake, and replacing it with the museum. Hobson said that plan would create 12 additional acres of parkland.

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The plan requires the borrowing of nearly $1.2 billion to replace the demolished structure, extending five taxes beyond their expiration date and state approval. The museum itself would be paid for by Lucas at a cost of $743 million.

“We don’t think it’s appropriate to exchange building on lakefront land for other things — even if it’s park land. It’s inappropriate to build on public trust land,” Friends of the Parks executive director Juanita Irizarry told the Chicago Sun-Times.

“Mr. Lucas may leave. That is ultimately his decision. But there are many other viable sites. Chicagoans should not be held hostage to one man’s desires,” she said. “The public trust must be protected and we will continue to fight for our lakefront to remain open, free and clear.”

Lucas chose Chicago over San Francisco for the museum after saying the city was “doodling around,” while Chicago officials aggressively pursued the project.

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