Just weeks before Hillary Clinton kicked off her campaign for president on Roosevelt Island, a Clinton family loyalist quietly parted ways with the powerful clan. Doug Band, a man once so close to President Bill Clinton that he was considered a surrogate son, left the Clinton Foundation, where he had various board appointments, The Post has learned. Band declined to comment, except to confirm he resigned his position last month. The departure marks the end of a complicated relationship between Band’s controversial consultant corporation, Teneo, and the Clintons.

And while the Clinton Foundation has been under fire for allegedly trading millions of dollars in donations for access to Bill and Hillary Clinton when she was secretary of state, Teneo’s role is less well-known. But Teneo played a part in what author Daniel Halper in his 2014 book “Clinton Inc.,” described as a vast money-making machine. “I think Teneo is not just emblematic of how Clinton Inc. works, it shows the political and financial mess that this whole thing has created,” Halper told The Post.

In a preview of the Clinton Foundation scandals that have dogged Hillary Clinton this year, The New Republic noted the suspicious nature of Band’s work in a 2013 article. “There’s an undertow of transactionalism in the glittering annual dinners, the fixation on celebrity and a certain contingent of donors whose charitable contributions and business interests occupy an uncomfortable proximity. More than anyone else except [Bill] Clinton himself, Band is responsible for creating this culture. And not only did he create it, he has thrived in it.”

Get Rich Quick

Now headquartered on the 45th floor of the Citigroup Center in Manhattan, and with offices around the world, Teneo — Latin for “to guide” — started more modestly in 2009 by business consultant Paul Keary.

Band and Declan Kelly, who had been US economic envoy to Northern Ireland in Hillary Clinton’s State Department, joined the firm in 2011, turning it into a global powerhouse.

Band is a 42-year-old Florida native who started his career at 22 as an intern in the Clinton White House. He earned a law degree, worked his way up at the White House, eventually becoming indispensable to the president as his aide or “body man.” Band was constantly by the president’s side, carrying bags and keeping Clinton on schedule.

When Clinton left office in 2001, Band reportedly turned down a job at Goldman Sachs and stuck with the former president as his personal assistant. Band became the gatekeeper for those wanting access to Clinton. The two were so close that Band was at Clinton’s bedside when he had heart bypass surgery in 2004. It was Band who, in 2005, came up with the idea for the Clinton Global Initiative, a yearly meeting of business bigwigs and heads of state in Manhattan.

Band was paid by Clinton and, once the Global Initiative was up and running, he drew a salary of $110,000 to head the group. But he was also paid an undisclosed extra amount of money by Clinton benefactor Ron Burkle, who sent checks to SGRD, Band’s Florida-based LLC, The Wall Street Journal reported. It was an attempt to keep Band on board with Clinton and not flee to a more lucrative position, the newspaper reported.

Band got rich quickly. By 2003, he bought a $2.1 million condo at the Metropolitan Tower on West 57th Street. He sold it in 2008 for $4.1 million and moved to the tony Essex House on Central Park South, where he still lives in a sprawling apartment.

Band married investment banker Lily Rafii in 2007. Clinton attended the wedding in a Paris chateau even though Band had asked him not to come. “Not only did he come, he made this incredible speech,” Band told a Florida newspaper in 2009.

Band traveled the world with Clinton, even accompanying him to North Korea in 2009 to secure the release of two journalists.

Band, in his bio on the Teneo website, says he was “part of the negotiation team that handled all aspects of Hillary Clinton’s becoming secretary of state.”

Clinton told The Washington Post in 2008, “I’m amazed he still works for me because he could make a lot more money somewhere else.”

‘Promise of Access’

In 2011, Band did branch out on his own, joining the fledgling Teneo and recruiting Bill Clinton to be a member of the advisory board. Clients paid staggering monthly retainers — up to $250,000 — to Band’s company. They were reportedly encouraged to give to the Clinton Foundation and, in turn, foundation donors were encouraged to use the services of Teneo. “The idea for Teneo was to have Fortune 400 companies pay large monthly stipends in exchange for access to Band, Clinton and their massive international network. The group would ‘consult’ with the companies, offer strategic advice and help them overcome issues in various countries across the globe,” Halper wrote in “Clinton Inc.”

But a former Teneo employee told Halper that what the clients really got was nothing, other than an “implicit promise of access to Clinton.”

In addition to Clinton, former British Prime Minister Tony Blair, former US Sen. George Mitchell and Ed Rollins, Ronald Reagan’s campaign manager, all came on board at Teneo.

Clinton was the key to Teneo’s success. “The two needed the president,” a source told Halper. “It was he who they were selling to their corporate clients. Or, more precisely, it was their proximity to power — President Clinton, and his wife, who was then secretary of state — and their own Rolodexes, which were a natural extension of the work they had done over the years for the Clintons.” Clients included Bank of America, Dow Chemical, UBS Wealth Management and Coca-Cola.

In exchange, Bill Clinton was given a contract with Teneo worth $3.5 million, Halper said. It is unclear, however, how much Clinton was actually paid.

The Chelsea Problem

Chelsea Clinton and her husband, Marc Mezvinsky, also wanted to muscle in on the action and asked for an equity stake in the company, Halper reported. But Band refused, seeing too much of a potential conflict in doing business with the daughter of the secretary of state. There may have been some “sibling” rivalry between Band and Chelsea Clinton.

In 2008, Band told restaurant owner Nino Selimaj to take down Chelsea’s photo from the wall of Osso Buco saying the former first daughter was not a public figure, according to New York magazine. In the end, Bill Clinton’s tenure at Teneo was short-lived.

The Post reported in December 2011 that Teneo had been advising MF Global, the doomed international brokerage firm headed by former New Jersey Gov. Jon Corzine. The firm paid Teneo an eye-popping $125,000 a month as it was imploding and losing millions for its investors.

Although Clinton’s office insisted the former president was not profiting from the MF Global arrangement, Hillary Clinton was said to be furious over the controversy. By February 2012, Clinton stepped down from Teneo. Shortly before he severed ties with the company, Clinton reportedly started to resent how Band and his partner Declan Kelly threw his name around to inflate Teneo’s importance. In one reported instance, Kelly seemed to take public credit for getting Clinton invited to speak at an economic forum in Dublin. But the former president had actually been invited by the Irish prime minister and was said to explode in anger at the suggestion that Teneo had somehow brokered his participation at the event.

But the connection to the Clintons continued. In June 2012, Hillary Clinton’s senior aide Huma Abedin began working as a part-time consultant to Teneo during her final months at the State Department.

Abedin, the wife of disgraced former Congressman Anthony Weiner, was designated a “special government employee,” which allowed her to both work for the State Department and to hold outside gigs. She also consulted for the Clinton Foundation and for Hillary Clinton.

Once the arrangement became known, there was criticism that there was overlap between a private firm and the inner workings of the State Department.

A source close to the negotiations told The Post that the deal came about as a way to help Abedin financially after her husband resigned in the wake of a sexting scandal in June 2011. “The truth is people felt sorry for Huma,” the source said. Asked if Abedin provided any inside intelligence about the State Department for Teneo, the source denied it. “People watch too much ‘House of Cards.’ ”

After Huma’s arrangement with Teneo came to light, Sen. Chuck Grassley, an Iowa Republican, asked the Government Accountability Office to conduct a review of the special government employee exception.

New Business

While it’s not clear whether Band or Teneo will play a part in Hillary Clinton’s presidential campaign, the company has continued to wield influence on a global scale without Bill Clinton on the board. Its website says its executives are involved in everything from sorting out issues around the Greek financial meltdown to working to leverage economic opportunities in Africa. It recently opened offices in the Far East and Brazil.

Tax filings show that Band was last paid by the Clinton Foundation in 2012, when he got $53,000. He remained linked to a European arm of the Clinton Foundation until stepping down last month.

A source told The Post that it became increasingly difficult for Clinton loyalists like Band to work with the Foundation after Chelsea Clinton was brought on board. “She wanted to be famous and rich and have a place to go,” said the source, adding that Chelsea was too inexperienced for the job. “It just didn’t make any sense.”