For more than a year, powerhouse Chicago Ald. Edward M. Burke had been trying to land the developer of Chicago’s Old Main Post Office as a client for his private law firm.

By October 2017, he’d had enough. He found himself alone with Ald. Danny Solis — a secret federal informant wearing a wire. Burke’s anger boiled over. He told Solis the developers “can go f--- themselves.” Then, Solis told him the company’s TIF funding would soon land in front of Burke’s stronghold, the Finance Committee.

“Well, good luck getting it on the agenda,” Burke allegedly said.

Now, Chicago’s longest-serving alderman has been charged with racketeering and bribery in a stunning, highly anticipated 59-page federal indictment filled with detailed allegations of classic Chicago graft. It not only accuses Burke, 75, of using his position to steer legal business to his private firm, but it also alleges he used the City of Chicago as a criminal “enterprise” as part of the racketeering charge — a law first devised decades ago to combat mobsters and organized crime.

One former federal prosecutor called the indictment “a watershed.” Mayor Lori Lightfoot called on Burke to resign immediately. In his own statement, Burke called the charges “unfounded” and predicted a jury will vindicate him.

The indictment showcases for the first time the undercover work of Solis, the former 25th Ward alderman whose cooperation with federal prosecutors was first reported by the Chicago Sun-Times in January. The indictment quotes several conversations between Burke and Solis about the Post Office developer, in which Burke complained, “the cash register has not rung yet.” He also asked, “did we land . . . the tuna?”

“So did we land the, uh, the tuna?” Ald. Burke allegedly asked about one developer he was targeting for legal work.

Solis, who was chairman of the City Council’s Zoning Committee, allegedly acted as a middleman in Burke’s shakedown, taking cues from law enforcement along the way.

The indictment revolves around four schemes, two of which involve iconic Chicago landmarks — the Old Post Office straddling the Eisenhower Expressway and the Field Museum. In addition to the Post Office scheme, Burke is accused of trying to block an admission fee hike at the museum, all because he wasn’t getting an answer about a museum internship for the daughter of former Ald. Terry Gabinski.

The indictment also lays out a previously charged shakedown involving a Burger King at 41st and Pulaski, as well as a scheme charged last month involving developer Charles Cui’s redevelopment project on the Northwest Side.

Charged along with Burke are his top political aide, ward worker Peter J. Andrews — accused of attempted extortion and lying to the FBI among other crimes — and developer Cui, who is accused of bribery and lying to the FBI.

Burke and Andrews are set to be arraigned Tuesday. Lawyers for Burke, Andrews and Cui either could not be reached or declined to comment. But Burke released a statement.

Burke allegedly told one alderman helping get him business he was “a believer in sharing the wealth.”

“For over 50 years, Ed Burke has served the citizens of the 14th Ward and the City of Chicago honorably and tirelessly,” the statement said. “His accomplishments on behalf of the community and his constituents are notable and many. Any suggestion that Ald. Burke abused his position as a public official for personal gain is simply not true. The charges are unfounded and not based on actual evidence. We welcome the opportunity to present the complete picture and all the facts to a jury. We are confident that when that happens, Ed Burke will be vindicated.”

Lightfoot called the allegations “alarming.”

“Ald. Burke must resign immediately,” Lightfoot said. “Given the serious criminal liability he faces, Ald. Burke can no longer continue to do his job honorably or effectively.”

Lightfoot also vowed to investigate whether any city employees or vendors helped Burke in his schemes and take appropriate action. The indictment alleges Burke leaned on top city employees for favors.

Burke was re-elected in February, just more than a month after he was initially charged with attempted extortion. However, the federal investigation has cost him control of the Finance Committee.

Andrews, 69, has been Burke’s top political operative for decades, helping circulate petitions for Burke’s re-election earlier this year. He is a retired Chicago Park District plumber who has an annual pension of $88,637.

Fifteen years ago, Andrews’ wife was listed as co-owner of the largest-female owned trucking company in the city’s scandal-plagued Hired Truck Program in which the administration of Mayor Richard M. Daley spent $40 million a year hiring private trucking companies that did little or no work on city projects. Base Trucking got paid more than $3.4 million between 1999 and early 2004 when a Sun-Times investigation led Daley to shut the program down as 49 people were indicted on criminal charges. No charges were filed against Base Trucking or its owners.

A business that needed something from the City Council but was stiffing Burke on business? “Well, good luck getting it on the agenda,” Burke allegedly said.

601W Companies, the developer of the Old Post Office allegedly targeted by Burke, released a statement referring to itself as “the victim of a corrupt solicitation by Ald. Burke.” The firm is voluntarily assisting the feds, a fact the Sun-Times first reported earlier this year. A Field Museum spokeswoman declined to comment.

The Post Office scheme dated to August 2016, when Burke allegedly first asked Solis to recommend his law firm, Klafter & Burke, to 601W Companies. Solis agreed, and the two men discussed how Solis would essentially get a kickback for any business he brought Burke. A month later, Burke allegedly told Solis he was a “believer in sharing the wealth.”

In an October 2016 meeting with the company’s representatives to discuss the Post Office project, Burke allegedly assured them there weren’t “too many people around town that we don’t know.”

The following month, Solis allegedly asked Burke how he would be paid for bringing clients to Burke’s firm. Burke suggested a payment could be made through a lawyer, or Solis could be paid as a “marketing representative.” Then, in December 2016, the feds prompted Solis to tell Burke his law firm would be hired if he helped sort out issues at the Old Post Office with Amtrak. Burke allegedly replied, “Okay, great.”

In January 2017, Burke allegedly told Solis he wouldn’t take any action benefitting 601W or its associate in connection with the Post Office project unless the associate hired his law firm. That’s when he allegedly told Solis that “the cash register has not rung yet.”

When 601W’s real estate management company had a problem that needed to be resolved with the Water Department and Amtrak in May 2017, Burke allegedly told Solis he had not heard about “getting hired to do the tax work” so Burke was not “motivated” to help. A week later, Burke allegedly asked Solis, “so, did we land the, uh, the tuna?” Then, prompted by law enforcement, Solis told Burke the company’s associate had agreed to provide future tax work to Klafter & Burke.

Burke allegedly promised Solis a “day of accounting” if his firm was retained.

However, October rolled around, and Burke’s firm still had not been hired. Burke and Solis met in Solis’ office with representatives of 601W, who explained the company needed TIF funding. Afterward, when Burke and Solis were alone, Burke “expressed anger that his law firm had not been hired,” according to the indictment.

Burke allegedly told Solis he was not “fond of the way they’ve conducted themselves up until this point, and as far as I’m concerned they can go f--- themselves.”

Finally, in August 2018, Burke apparently left Solis a voicemail in which he confirmed a 601W representative had contacted him about hiring Klafter & Burke. Solis asked Burke if he would support TIF funding for the Post Office project, and Burke allegedly replied, “absolutely.” The TIF proposal sailed through Burke’s Finance Committee on Sept. 17, 2018, and the City Council on Sept. 20, 2018.

Meanwhile, the indictment also alleges that Burke threatened in September 2017 to call the president of Chicago’s Park District Board and oppose an admission fee increase at the Field Museum because it had failed to respond to his earlier effort to land an internship for former Ald. Gabinski’s daughter. Burke received an email from a Field Museum executive giving Gabinski’s daughter a chance to apply for a full-time job.

Ultimately, Gabinski’s daughter told the museum she was “declining consideration for the position.” Neither Gabinski could not be reached Thursday.

All of this lands almost six months to the day after the FBI raided Burke’s City Hall office, rocking Chicago in the midst of an election that put Lightfoot, a former federal prosecutor, in the mayor’s office. Lightfoot has promised reform and moved to end the so-called tradition of aldermanic privilege. Just Wednesday, she tangled with Burke in her first City Council meeting since taking office, quickly dispatching him as he objected to some of her administration’s rule changes.

Former federal prosecutor Jeffrey Cramer called Thursday’s charges “a watershed indictment” that for the first time examines “the intricacies of the aldermanic power” and “how it was abused here.” Cramer is now a managing director in Chicago for Berkeley Research Group.

He said the indictment and Lightfoot’s election could be a “one-two punch” that could lead to “real reform and real change.”

“This indictment is going to help facilitate that,” he said.