WASHINGTON -- U.S. President-elect Donald Trump has called a report purportedly detailing compromising information gathered by Russia "fake news" and "phony stuff" crafted by "sick people."
Trump's remarks came during a news conference at his Manhattan offices on January 11 and followed a series of events focusing on the role that Russia may have played in influencing the U.S. presidential election.
Those events culminated on January 10 with news reports that said a classified intelligence dossier given to President Barack Obama last week contained potentially compromising personal and financial information about Trump.
Trump, who has pledged to seek better ties with Moscow, denied the assertions in a series of earlier posts to Twitter on January 11 and criticized U.S. intelligence agencies for "allowing" the leak, which he described as "one last shot at me."
"Are we living in Nazi Germany?" he wrote.
Top intelligence officials found the unverified claims sufficiently credible to include them in the briefing and the FBI was reportedly investigating their validity, multiple reports said.
The claims were part of a two-page synopsis appended to a report on alleged Russian interference in the U.S. presidential election, an appendix that was considered so sensitive that it was only shared with Obama, Trump, and eight Congressional leaders in briefings last week, CNN said.
The New York Times, Reuters, AP, and other news organizations reported similar information, citing U.S. officials who spoke on the condition of anonymity.
Trump first responded on January 10 with a tweet that said: "FAKE NEWS -- A TOTAL POLITICAL WITCH HUNT!"
In one of his tweets on January 11, he said: "Russia has never tried to use leverage over me. I HAVE NOTHING TO DO WITH RUSSIA -- NO DEALS, NO LOANS, NO NOTHING!”
In another, he also referred to the Kremlin's denial of the story. Earlier in the day, Russian President Vladimir Putin's spokesman, Dmitry Peskov, said that "the Kremlin has no compromising dossier on Trump" and that any claims to the contrary are "absolute fantasy."
The potentially explosive allegations were originally compiled by an unnamed former British MI6 intelligence operative, whose past work U.S. intelligence officials consider credible, CNN said, citing "multiple U.S. officials with direct knowledge of the briefings." He was posted in Russia in the 1990s and now runs a private intelligence-gathering firm.
The operative's investigations were initially funded by groups and donors supporting Republican opponents of Trump during the Republican Party primaries in 2016, CNN said. The network added that that once Trump became the Republican nominee, further investigation was funded by groups and donors supporting Democratic Party candidate Hillary Clinton.
The report charges that Russia's Federal Security Service (FSB) "has compromised Trump through his activities in Moscow sufficiently to be able to blackmail him."
It describes sexually explicit videos involving prostitutes allegedly filmed with Trump during a 2013 trip to Moscow.
It also claims that Trump surrogates and Russian government officials were in regular communication during the campaign. It describes several alleged meetings at which it says the hacking of Democratic Party e-mails and other campaign issues were discussed.
The document quotes an unidentified Russian official as purportedly saying the e-mails were leaked "with the full knowledge and support" of the Trump team and that Trump had agreed in return "to sideline Russian intervention in Ukraine as a campaign issue."
One of the meetings allegedly involved Trump lawyer Michael Cohen and took place in Prague in August or September. Cohen said on Twitter that he had never been to Prague.
The document suggests that Putin's government for years has looked for ways to influence Trump, who has traveled repeatedly to Moscow to investigate real estate deals or to oversee the Miss Universe competition, which he owned for a time.
CNN said it had learned that Republican U.S. Senator John McCain gave FBI chief James Comey a copy of the memos comprising the report in December.
There was no immediate comment from the FSB on the allegations, which came four days after U.S. intelligence agencies said they concluded that Putin ordered a hacking campaign that aimed to help Trump and influence the U.S. election.
Russian State Duma Deputy Nikolai Kovalyov, a former director of the FSB, asserted that "there is no compromising material" on Trump.
"Who is interested in compromising material on a man who came here to organize a beauty contest?" lower parliament-house member Kovalyov told Interfax. "I can tell you from my professional experience that Russia does not have such practices."
Sexually explicit videos have been leaked in the past in Russia in apparent efforts to discredit officials or politicians.
With reporting by CNN, AP, Interfax, Reuters, The Guardian, and The New York Times