Just over a week before Trump takes office, the United States has been rocked by unsubstantiated claims that his aides colluded with the Kremlin to win the election -- and that Russia has compromising sexual material on Trump.
"I think it's a disgrace that information would be let out," Trump said, training fire on media outlets that published the allegations and the intelligence agencies who he suggested may have leaked it.
"It's all fake news. It's phony stuff. It didn't happen," he said in his first press conference in nearly six months.
"It was a group of opponents that got together, sick people, and they put that crap together."
It "was released by maybe the intelligence agencies, who knows, but maybe the intelligence agencies, which would be a tremendous blot on their record," Trump said, later saying it was "disgraceful."
On Twitter, he decried a political "witch hunt" against him and asked: "Are we living in Nazi Germany?"
'No dealings with Russia'
The US intelligence community has concluded Moscow interfered in the November election in a bid to tip the race in Trump's favor.
Intelligence chiefs last week also presented America's incoming 45th president, as well as current President Barack Obama, with a two-page synopsis on the potentially embarrassing but unsubstantiated allegations involving Russia, according to CNN and The New York Times, who cited multiple unnamed US officials with knowledge of the meeting.
The Kremlin has dismissed the dossier -- drawn up by a former British intelligence agent hired to do "opposition research" on Trump during the presidential campaign and published by US media outlet BuzzFeed -- as a "total fake" aimed at damaging bilateral ties.
Trump spokesman Sean Spicer turned his fire on BuzzFeed.
"It's frankly outrageous and highly irresponsible for a left-wing blog that was openly hostile to the president-elect's campaign to drop highly salacious and flat-out false information on the internet just days before he takes the oath of office," he said, introducing Trump.
Trump later called BuzzFeed "a failing pile of garbage" and warned they would "suffer the consequences."
"I have no dealings with Russia. I have no deals in Russia. I have no deals that could happen in Russia, because we've stayed away. And I have no loans with Russia," Trump then said.
Even before the allegations surfaced widely in US media on Tuesday, Trump's Republican allies have become increasingly uneasy about Russia's role in the election, with calls for an independent investigation growing.
The issue threatens to sap legitimacy from the Trump administration before it even enters the Oval Office.
Trump fanned the flames by again downplaying Russia's influence in the outcome of the election and defended his openness towards Russian President Vladimir Putin.
"As far as hacking, I think it was Russia, but I also think we've been hacked by other countries, other people."
"If Putin likes Donald Trump, I consider that an asset, not a liability, because we have a horrible relationship with Russia," Trump said.
"I don't know that I'm going to get along with Vladimir Putin. I hope I do. But there's a good chance I won't."
WATCH: Trump briefed on Russia dossier
Without corroborating its contents, BuzzFeed published a 35-page dossier of memos on which the synopsis presented to Trump is based.
The memos, which had been circulating in Washington for months, describe sex videos involving prostitutes filmed during a 2013 visit by Trump to a luxury Moscow hotel, supposedly as a potential means for blackmail.
They also suggest Russian officials proposed lucrative deals in order to win influence over the real estate magnate.
Trump was reportedly informed of the existence of the dossier -- and its salacious details -- last Friday when he received a briefing from US intelligence chiefs on alleged Russian interference in the presidential election.
The classified two-page synopsis reportedly included allegations that there was a regular flow of information during the campaign between Trump surrogates and Russian government intermediaries, which a Trump aide denied.
On Wednesday, Trump would not comment on the classified briefing, but did say he had read some of the information "outside of the briefing," without specifying which parts.
"The Kremlin does not have compromising information on Trump," Russian President Vladimir Putin's spokesman Dmitry Peskov telling journalists.
The Kremlin spokesman called the dossier a "total fake" and "an obvious attempt to harm our bilateral relations."
No more rule book
No other US president-elect in modern times has waited so long to go formally before the media, considered important to shore up public accountability, yet Trump has reveled in ripping up the rule book.
During his last press conference -- before the election -- he invited Russia to hack his Democratic opponents.
The New York billionaire, never previously elected to office, has preferred to make off-the-cuff statements, punch out incendiary tweets and call out anyone who dares cross him -- from Oscar-winning actress Meryl Streep to an Indiana union leader.
While he has conducted one-on-one interviews with select media and taken questions from reporters in informal settings, his performance at the press conference will be scrutinized, as polls show his already bleak approval ratings deteriorate further as the clock ticks down to inauguration day on January 20.