MIAMI — One day in late May 2016, Roger Stone — the political dark sorcerer and longtime confidant of Donald Trump — slipped into his Jaguar and headed out to meet a man with a Make America Great Again hat and a viscous Russian accent.

The man, who called himself Henry Greenberg, offered damaging information about Hillary Clinton, Trump’s presumptive Democratic opponent in the upcoming presidential election, according to Stone — who spoke about the previously unreported incident in interviews with The Washington Post. Greenberg, who did not reveal the information he claimed to possess, wanted Trump to pay $2 million for the political dirt, Stone said.

“You don’t understand Donald Trump,” Stone recalled saying before rejecting the offer at a restaurant in the Russian-expat magnet of Sunny Isles, Fla. “He doesn’t pay for anything.”

Later, Stone got a text message from Michael Caputo, a Trump campaign communications official who’d arranged the meeting after Greenberg had approached Caputo’s Russian-immigrant business partner.

“How crazy is the Russian?” Caputo wrote according to a text message reviewed by The Post. Noting that Greenberg wanted “big” money, Stone replied: “waste of time.”

Two years later, the brief sit-down in Florida has resurfaced as part of special counsel Robert Mueller III’s sprawling investigation of Russian interference in the 2016 presidential campaign, according to Caputo. Caputo said he was asked about the meeting by prosecutors during a sometimes-heated questioning session last month.

Stone and Caputo, who did not previously disclose the meeting to congressional investigators, now say they believe they were the targets of a setup by U.S. law enforcement officials hostile to Trump.

They cite records — independently examined by The Post — showing that the man who approached Stone is actually a Russian national who has claimed to work as an FBI informant.

Interviews and additional documents show that Greenberg has at times used the name Henry Oknyansky. Under that name, he claimed in a 2015 court filing related to his immigration status that he had provided information to the FBI for 17 years. He attached records showing that the government had granted him special permission to enter the U.S. because his presence represented a “significant public benefit.”

There is no evidence that Greenberg was working with the FBI in his interactions with Stone, and in his court filing, Greenberg said that he had stopped his FBI cooperation sometime after 2013.

Greenberg, in text messages with The Post, denied that he had been acting on the FBI’s behalf when he met with Stone.

An FBI spokeswoman declined to comment, as did a spokesman for Mueller’s office.

The meeting took place two months earlier than federal officials have said a counterintelligence operation was officially opened and before WikiLeaks began releasing hacked Democratic emails.

It came in the same time period as other episodes in which Russian interests approached the Trump campaign. A few weeks earlier, Trump campaign foreign policy adviser George Papadopoulos was told in London that the Russians had dirt on Clinton. And it was two weeks before the sit-down between Donald Trump Jr. at Trump Tower with a Russian lawyer who he had been told could offer information that would hurt Clinton as part of a Russian government effort to help his father.

Trump and his allies have said the meetings were inconsequential, and there was no collusion.

Stone and Caputo’s interactions with Greenberg mean that at least 11 Trump associates or campaign officials have acknowledged interactions with a Russian during the election season or presidential transition. Those interactions have become public in the year and a half since a Trump spokeswoman said that no one associated with the campaign had communications with Russians or other foreign entities.

It is not clear how seriously investigators are taking the Florida meeting. Caputo said that prosecutors during his interview seemed to have intense interest in the interaction as well as the role of Greenberg.

Reached by phone, Greenberg, 59, initially denied Stone’s account of a meeting.

“This is wrong information,” Greenberg said.

Later, in text messages to a Post reporter, Greenberg changed his story, acknowledging that he’d met with Stone and providing a skeletal account of the encounter that matched Stone’s in some ways. Unprompted, Greenberg used essentially the same language as Stone to describe Stone’s reaction: “Trump will never pay for anything.”

Stone said Greenberg was alone at the meeting. But Greenberg said he was accompanied by a Ukrainian friend he identified only as Alexei, who he said had been fired from a job with the Clinton Foundation, a global charitable organization founded by Hillary Clinton’s husband, former president Bill Clinton. A Clinton Foundation spokesman said the foundation has never employed a man with the first name of Alexei.

“He was very upset, and he wants to tell his story,” Greenberg said in a text. “He told Mr. Stone what he knew and what he want.”

Greenberg denied that he asked for money, saying that it was his friend who spoke with Stone.

Trump and his allies previously accused the FBI of unfairly targeting his campaign following revelations that another FBI informant, Cambridge University professor Stefan A. Halper, approached Papadopoulos and two other campaign advisers starting in July 2016 to gather information about their possible ties to Russia.

“If you believe that (Greenberg) took time off from his long career as an FBI informant to reach out to us in his spare time, I have a bridge in Brooklyn that I want to sell you,” Caputo said in an interview.

In a separate interview, Stone said: “I didn’t realize it was an FBI sting operation at the time, but it sure looks like one now.”

The Florida meeting adds another layer of complexity to Stone’s involvement in the Russia probe. For months, as several of Stone’s employees and associates have been subpoenaed or have appeared before the Mueller grand jury, it has been clear that the special counsel has been scrutinizing repeated claims by Stone that he communicated with WikiLeaks via a back-channel source before the group’s 2016 release of hacked Democratic Party emails.

Stone has said it’s possible he will be indicted, speculating that Mueller might charge him with a crime unrelated to the election in order to silence him. He said he anticipates that his meeting with Greenberg could be used in an attempt to pressure him to testify against Trump — something he says he would never do.

Last year, in a videotaped interview with The Post, Stone denied having any contacts with Russians during the campaign.

“I’ve never been to Russia. I didn’t talk to anybody who was identifiably Russian during the two-year run-up to this campaign,” he said. “I very definitely can’t think of anybody who might have been a Russian without my knowledge. It’s a canard.”

Stone and Caputo said in separate interviews that they also did not disclose the Greenberg meeting during testimony before the House Permanent Select Committee on Intelligence because they had forgotten about an incident that Stone calls unimportant “due diligence” that would have been “political malpractice” not to explore.

Caputo said that he was asked during a session with the committee in July whether he’d ever been offered information about the Clinton campaign by a Russian, and he either answered “no” or that he could not recall.

However, Stone and Caputo said their memories were refreshed by text messages that Caputo said he no longer has in his possession but was shown during a May 2 interview.

Caputo’s attorney on Friday sent a letter amending his House testimony, and he plans to present Caputo’s account of the Greenberg incident to the Office of Inspector General for the Department of Justice, which has announced it is examining the FBI’s use of informants during the Russia probe. Stone said his attorney has done the same.

Documents and interviews reveal a quirk-filled story that spans three decades and two continents. It touches down in locales as distinct as a hipster Miami art gallery and a riverfront construction site. But, like so much of the drama swirling around the 2016 election, its roots lie far away from American ballot boxes — in the Russian capital of Moscow.

Though they never met, both Caputo and Greenberg lived heady existences in Moscow in the years after the collapse of the Soviet Union, a period when the city had a frisson of artistic and creative energy that Caputo compares to “Paris of the 1920s, but with Kalashnikovs.” Caputo had moved to Russia to develop a Rock-the-Vote-style campaign for Russian President Boris Yeltsin.

Greenberg was already a familiar figure in the city’s social whirl. He married a Russian actress and moved to Los Angeles. Court records show that, after being charged in 1994 with assault with a deadly weapon, he entered a plea in which he was convicted without accepting guilt.

According to a declaration he filed in court, Greenberg spent almost two years in the custody of the U.S. immigration service. He said he decided in 2000 to return to Russia, where, according to interviews and local media coverage, he resumed a glamorous life.

For a time, he shared an apartment at a fashionable Moscow address with John Daly, a producer of hit films including “Terminator,” and he was well known by expats from the Moscow club scene.

“He was an up and down kind of guy. Charming. Very ingratiating and personal,” said Edward Bass, a movie producer who spent time with Greenberg in Moscow in that time.

According to accounts in Russian media, he was arrested in 2002 and charged with a decade-old $2.7 million fraud. The Moscow Times reported that authorities found three passports with false names in his apartment and photographs that appeared to show him posing with movie directors Steven Spielberg and Oliver Stone.

The Post was unable to determine the outcome of the case from public records. Greenberg denied wrongdoing, saying he was not convicted, and the case was closed.

Greenberg returned to the U.S., according to immigration records that he submitted as part of his federal court filing in 2015.

He attached to the statement government documents outlining his immigration history.

Between 2008 and 2012, the records show, he repeatedly was extended permission to enter the U.S. under a so-called “significant public benefit parole.” The documents list an FBI agent as a contact person. The agent declined to comment.

Immigration lawyer David Leopold, former president of American Immigration Lawyers Association, said the documents described an immigration history generally consistent with Greenberg’s claims that he had been allowed to enter the U.S. to assist law enforcement.

In a 2015 court declaration, Greenberg — using the last name Oknyansky — said he’d been giving information to the FBI since returning to Russia from the U.S. in 2000.

“Wherever I was, from Iran to North Korea, I always send information to” the FBI, he wrote. “I cooperated with the FBI for 17 years, often put my life in danger. Based on my information, there is so many arrests criminal from drugs and human trafficking, money laundering and insurance frauds.”

Greenberg did not respond to questions about his use of multiple names but said in a text that he had worked for the “federal government” for 17 years.

“I risked my life and put myself in danger to do so, as you can imagine,” he said.

By May 2016, Greenberg was in the midst of an eventually unsuccessful zoning fight to open a restaurant on the Miami River, according to public records. He showed up without an invitation at a gallery opening organized by Caputo’s public relations firm, according to Caputo’s business partner, Sergey “George” Petrushin.

Greenberg approached Petrushin and invited him to check out the possible restaurant site the next day, Petrushin said. According to Petrushin, Greenberg eventually said that he knew Petrushin was partners with Caputo and that he had information he wanted to share that would be helpful to Trump’s campaign.

Petrushin called Caputo, and handed the phone to Greenberg to make his pitch.

At the time, Caputo said, Russia was not a major campaign issue, and the man’s accent raised no red flags for him.

“I said, ‘Let me get somebody to vet it for you,’” Caputo recalls saying.

Caputo knew just the guy: Roger Stone.

Stone had spent decades trying to persuade Trump to run for president. In the spring of 2016, Stone was no longer with the campaign — but he remained in touch with Trump and some in his orbit.

When Stone arrived at the restaurant in Sunny Isles, he said, Greenberg was wearing a Make America Great Again T-shirt and hat. On his phone, Greenberg pulled up a photo of himself with Trump at a rally, Stone said.

“We really want to help Trump,” Stone recalled Greenberg saying during the brief encounter.

By Greenberg’s account, he had limited contact with Stone, sitting at a nearby table while his friend Alexei conducted the meeting. “Alexei talk to Mr. Stone, not me,” he wrote. He added that he believes Alexei has moved back to Ukraine, and they are not in contact.

When Caputo followed up with Stone via text to ask if “anything at all interesting” took place, Stone responded with a single word: “No.”

Helderman reported from Washington. The Washington Post’s Alice Crites and Devlin Barrett in Washington and Natasha Abbakumova in Moscow contributed to this report.