During the 2016 presidential campaign, the founder of the opposition research firm behind the Steele dossier tipped a major news network off to Sergei Millian, a Belarus-born businessman who has been identified as a source for the salacious claims made in the dossier. Glenn Simpson, the founder of Fusion GPS, provided the tip to ABC News despite having doubts about the veracity of Millian’s claims about President Donald Trump.

That’s according to “Russian Roullette: The Inside Story of Putin’s War on America and the Election of Donald Trump,” a book written by Michael Isikoff and David Corn that hit shelves on Tuesday. The two veteran journalists report that Simpson told ABC News about Millian, the chairman of the Russian-American Chamber of Commerce, during the heart of the 2016 campaign.

“Simpson would later learn from Steele the identity of Source D, the main source for the ‘golden showers’ allegation: It was Sergei Millian,” the book reads. 

“Source D” is described in a June 20, 2016, memo written by Steele as “a close associate of TRUMP who had organized and managed his recent trips to Moscow.” The dossier claims that the source — now known as Millian — confirmed that the Kremlin had been feeding the Trump team intelligence on Clinton. 

The information had been “very helpful” to the campaign, Millian said.

He also provided shocking allegations about Trump’s activities in Moscow during a November 2013 trip to the Miss Universe pageant. Source D, aka Millian, was present in Moscow where Trump engaged in “perverted” conduct, according to the dossier. This conduct allegedly included employing prostitutes to perform a “golden showers” show in front of him in his hotel room. Trump wanted to defile the room because it was where former President Barack Obama and his wife Michelle had stayed years before, according to the dossier.

Isikoff and Corn report that Millian was not aware his comments were being used to spy on Trump. “Like all of those who had spoken to Steele’s collector, Millian was an unwitting source; he had no idea his conversation with the collector would be passed along to Trump’s political foes,” they wrote.

Reached by The Daily Caller News Foundation, Millian disputed Steele’s claims and the new book.

“It’s all garbage news,” he told TheDCNF.

“Never happened,” he added, saying that he “was not in Moscow on that night.”

Millian’s involvement in the dossier was of apparent concern to Simpson, according to “Russian Roulette.”

“The memo had described Millian as a Trump intimate, but there was no public evidence he was close to the mogul at that time or was in Moscow during the Miss Universe event,” the book reads. “Had Millian made something up or repeated rumors he had heard from others to impress Steele’s collector? Simpson had his doubts. He considered Millian a big talker.”

Those doubts did not stop Simpson from telling ABC News about Millian, whose real name is Siarhei Kukuts.

“For Simpson, Millian was now an investigative target. He tipped off ABC News, which conducted an on-air interview with Millian,” the book reads. It is unclear whether Simpson told ABC that Millian was a source for the dossier.

Ross, the investigative reporter at ABC, conducted the interview with Millian in July 2016. The interview largely flew under the radar, though it was cited in a few articles published before the election about Trump’s supposed ties to mysterious Russians. Though Millian is not Russian, he runs a trade group that caters to Russian businesses.

He was one of “very few people who have insider knowledge of Kremlin politics…who has been able to successfully integrate in American society,” Millian claimed.

Millian met Trump in Florida in 2008 and was an official broker for Trump Hollywood, he said. Trump has done “hundreds of millions of dollars” of business with Russians, he also claimed.

“Trump team, they realized that we have a lot of connections with Russian investors. And they noticed we bring a lot of investors from Russia,” Millian said.

Asked why Trump likes Russia, Millian responded with an answer that slightly mirrors the allegations in the dossier.

“He likes Russia because he likes beautiful Russian ladies,” Millian said in the awkward interview with Ross. “He likes talking to them, of course. And he likes to be able to make lot of money with Russians, yes, correct.”

Ross then quizzed Millian about any links he had to the Kremlin or to Russian spy services.

“Are you involved in any way with Russian intelligence agencies?” Ross asked.

“Absolutely, no,” said Millian.

Unknown at the time was Millian’s friendship with Trump campaign adviser George Papadopoulos. Papadopoulos has since pleaded guilty for lying to the FBI about contacts with Russian nationals. He was also told by a Russian-linked professor about emails that had been stolen from Democrats.

In his ABC interview, Millian denied sharing information with Russian government officials but acknowledged having friends in the Kremlin and discussing American politics with them.

“Usually if I meet top people in the Russian government, they invite me to the Kremlin for the reception, so of course I have a chance to talk to some presidential advisers and some of the top people,” said Millian.

The ABC News interview with Millian resurfaced shortly after Trump’s inauguration when the network — along with The Wall Street Journal — broke the story that Millian was “Source D” for the dossier.  Simpson was tight-lipped about Millian during his testimony in November before the House Permanent Select Committee on Intelligence. Asked by California Rep. Adam Schiff, a Democrat, whether Millian was a source, Simpson said: “I’m not in a position to get into the identity of the sources for the dossier for security reasons, primarily.”

Simpson also described research that Fusion GPS had done on Millian, though without noting he had provided some of the information to the media. Millian has kept a low profile since the release of the dossier, issuing vague denials about being a source for the dirty document. Congressional committees investing Russian interference have tried but failed to contact Millian for interviews.

Simpson, Steele and Steele’s business partner, Christopher Burrows, have all expressed reservations about the “golden showers” incident, according to Isikoff and Corn. Steele has lowered his degree of certainty that the incident happened. “It’s fifty-fifty,” he has told associates.

Follow Chuck on