Hillary Clinton's campaign and the Democratic National Committee helped bankroll research that led to the 'golden showers' dossier on Donald Trump.

Clinton's campaign lawyer Marc Elias hired research firm Fusion GPS back in April 2016 to look into allegations of Trump's ties to Russia, according to the Washington Post.

Fusion GPS, the Washington-based research firm, then hired former British intelligence officer Christopher Steele to dig up the unconfirmed dirt on Trump.

Clinton's lawyer and his law firm Perkins Coie continued to fund the research until October 2016 - just days before the presidential election.

The research was previously funded by an unknown anti-Trump Republican donor during the primary, but Clinton's campaign then paid for it to be finished.

Sources would not confirm how much was paid to Fusion GPS, but said the campaign and DNC shared the cost.

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Hillary Clinton's campaign and the Democratic National Committee helped pay for research that led to the 'golden showers' dossier on Donald Trump

The Clinton campaign paid Perkins Coie $5.6million legal fees during the period of June 2015 to December 2016, according to campaign finance records, while the DNC paid $3.6million in 'legal and compliance consulting', according to the Post. but it's unclear how much of that was related to Fusion GPS.

The FBI also is said to have agreed to pay Steele to continue gathering intelligence but reneged on the agreement after his cover was blown.

Steele's findings and research were then submitted to Elias via Fusion GPS, the Post reports. It is not clear what information, or how much of it, was provided to Clinton's campaign. It also isn't clear which people within Clinton's campaign and the DNC knew of Steel and Fusion GPS.

The research resulted in the now infamous dossier that came up with the discredited claims about Trump. The dossier has become a focus of congressional probes into Russian interference in last year's election.

Trump tweeted on Saturday that the FBI and Justice Department should 'immediately release who paid for it' after Fusion GPS co-founder Peter Fritsch and partner Thomas Catan last week invoked the US Constitution's Fifth Amendment, which protects Americans against self-incrimination.

The two men had been subpoenaed to appear in a closed-door session before the House Intelligence Committee but refused to speak at every turn.

Committee chair Rep. Devin Nunes has been trying to determine who paid Fusion GPS for the opposition research that formed the basis of the dossier.

'Officials behind the now discredited 'Dossier' plead the Fifth. Justice Department and/or FBI should immediately release who paid for it,' Trump tweeted.

Trump had also speculated on Twitter last week that the dossier may have been funded by Democratic officials.

'Workers of firm involved with the discredited and Fake Dossier take the 5th. Who paid for it, Russia, the FBI or the Dems (or all)?' Trump said last Thursday.

Fusion GPS, Elias and spokesmen for Clinton's campaign and the DNC would not comment.

Clinton's campaign lawyer Marc E. Elias (above in August 2016) hired research firm Fusion GPS back in April 2016 to look into allegations of Trump's ties to Russia

Clinton's lawyer continued to fund the firm's research into Trump until October 2016 - just days before the presidential election

Trump tweeted on Saturday that the FBI and Justice Department should 'immediately release who paid for it'

Prior to the Post report, Elias had earlier 'vigorously' denied being involved in the Trump dossier, according to New York Times reporter Ken Vogel.

'When I tried to report this story. Clinton campaign lawyer (Marc Elias) pushed back vigorously, saying 'You (or your sources) are wrong',' Vogel tweeted shortly after the Post report surfaced.

The dossier contends that the Russian government amassed compromising information about Trump but had also been engaged in a years-long effort to support and assist him.

Compiled by the British spy, Christopher Steele, the dossier circulated among Washington journalists last year until Buzzfeed first published it in January without verification.

Trump branded the entire document 'fake news.'

Among its claims are that Russian officials have videos of the president cavorting with prostitutes, which were filmed during Trump's 2013 visit to a luxury Moscow hotel for the Miss Universe contest

It also contains a highly unusual report, also never substantiated, that the call girls performed a 'golden shower' routine that involved them urinating on a hotel bed as a sign of disgust for then-president Barack Obama.

The FBI has worked to corroborate the document, and in a sign of its ongoing relevance to investigators, special counsel Robert Mueller's team - which is probing potential coordination between Russia and the Trump campaign - weeks ago questioned the former British spy who helped compile the claims in the dossier.

The dossier, compiled by British spy Christopher Steele, contends that the Russian government amassed compromising information about Trump but had also been engaged in a years-long effort to support and assist him

Fusion GPS co-founder Peter Fritsch (left) and partner Thomas Catan (right) took the Fifth on Wednesday rather than talking to Congress about the dossier

Prior to the Post report, Elias had earlier 'vigorously' denied being involved in the Trump dossier, according to New York Times reporter Ken Vogel