A new book out by Guardian journalist Luke Harding provides previously unknown details about the Trump dossier and its author, former British spy Christopher Steele.

Harding offers a sympathetic and largely uncritical look at Steele and the dossier, which was commissioned by opposition research firm Fusion GPS and funded by the Clinton campaign and DNC.

Steele’s 35-page report remains largely uncorroborated, and Trump and members of his campaign have denied the most salacious allegations laid out in the report.

While Harding defends the dossier against those denials, his book, “Collusion: Secret Meetings, Dirty Money, and How Russia Helped Donald Trump Win,” does help fill in some gaps in how Steele compiled his anti-Trump research, which BuzzFeed News published to much controversy on Jan. 10.

Here are a few revelations from the book, which hit shelves on Thursday.

Steele first began investigating Paul Manafort

According to Harding, after Fusion GPS hired Steele in spring 2016, the former MI6 officer began his project by investigating Trump campaign chairman Paul Manafort’s business activities.

Fusion took on the project after being hired in April 2016 by Perkins Coie, the law firm that represented the Clinton campaign and DNC.

“In early spring 2016, Simpson approached Steele. Steele started to scrutinize Paul Manafort, Trump’s new campaign manager,” writes Harding.

Manafort is mentioned only twice in the dossier. Steele alleges that he directed the Trump campaign effort to collude with Russian operatives.

Manafort left the campaign in Aug. 2016 after reports surfaced about his consulting work for a pro-Russia Ukrainian political party. He has since been indicted for money laundering by Special Counsel Robert Mueller.

New details about the surveillance warrant against Trump campaign adviser Carter Page

Harding reports new details about what information was included in a Justice Department application for a Foreign Intelligence Surveillance Act (FISA) warrant against Carter Page, a former Trump campaign adviser who had visited Moscow in July 2016 and is featured prominently in the dossier.

The Washington Post reported earlier this year that a FISA warrant was authorized against Page last September, just after he left the Trump campaign.

The evidence presented by the government for that warrant has remained a closely held secret, though there have been reports that the dossier was cited in the request. Page vehemently denies the allegations made against him in the dossier and has argued that the federal government broke the law by relying on Steele’s “dodgy dossier” to spy on him.

In the dossier, Steele alleges that Page, an energy consultant, met in secret with two Putin allies during his Moscow trip as part of the alleged campaign collusion scheme. The dossier also accuses Page of working with Manafort on the effort. Page has denied ever talking to Manafort or of meeting the Kremlin officials that the dossier alleges he colluded with.

According to Harding, the FISA application cited contacts that Page has had in the past with Russian operatives.

It has previously been reported that in 2013, Page, an energy consultant and former banker, was approached by a covert Russian spy as part of an apparent recruitment attempt. Page cooperated with the FBI in the case.

Page’s testimony was included in the FISA warrant application, according to Harding.

Harding also revealed that the FISA application cited “further meetings with Russian operatives that had not been publicly disclosed.”

The author did not elaborate on those meetings.

Dossier allegations about Page were shared with top lawmakers

The allegations about Page that were made in the dossier “figured prominently” in classified briefings provided to a small group of lawmakers in Aug. 2016, according to Harding.

“In a classified briefing to congressional leaders in late August Page’s name figured prominently. The CIA and FBI were sifting through a mount of intercept material featuring Page, much of it ‘Russians talking to Russians,’ according to one former National Security Council member,” Harding writes.

One of the lawmakers who received those briefings was then-Senate Minority Leader Harry Reid.

Reid would later send a letter to then-FBI Director James Comey referring to “disturbing” information he had learned about contacts between the Trump campaign and Russian operatives.

According to Harding, Reid was referring to the allegations made in the dossier about Page.

Clinton campaign member emailed reporter about Trump sex allegations

Harding reported that he was contacted by a member of the Clinton campaign who laid out allegations that Trump had used prostitutes in Moscow. Steele’s June 20, 2016 dossier memo makes similar unverified claims.

The outreach establishes for the first time that someone on the Clinton campaign attempted to peddle unfounded rumors about Trump to the press. Harding did not identify the campaign official.

He wrote: “In October an email written by a person in the Clinton camp reached my inbox. It set out some of the unproven allegations against Trump, including sex with prostitutes in Moscow. The email said the claims came from a source inside the FSB. This was not Steele’s work, but some of it echoes the dossier.”

Reporters at competing outlets cooperated on anti-Trump efforts

In the book, Harding describes how reporters at competing outlets rallied together as part of an effort to expose Trump’s alleged Russia ties.

“There was healthy competition still, but reporters on different titles began working together on some stories. There were formal press consortiums and ad hoc conversations between onetime rivals,” Harding writes.

“I talked to The New York Times, The Washington Post, the Financial Times in London, Reuters, Mother Jones, The Daily Beast, CNN, and others. Such conversations took place in New York, Washington, London, Munich, and Sarajevo. Some happened in glossy conference rooms, others in the corners of pubs over warm ale.”

Steele did not want BuzzFeed to publish the dossier

Steele has revealed in London court filings that he did not distribute the dossier to anyone outside of Fusion GPS, British intelligence, Arizona Sen. John McCain and one of his associates, David Kramer.

And according to Harding’s book, Steele appeared to have been upset by BuzzFeed’s decision to publish the document.

“Steele hadn’t wanted his dossier to be published. Buzzfeed were ‘tossers,'” a friend of Steele’s told Harding.

Fusion GPS founder Glenn Simpson gave a copy of the dossier to McCain

It has been previously reported that McCain was aware of the dossier before it was published by BuzzFeed on Jan. 10. He was told of its existence in Nov. 2016 by Sir Andrew Wood, a former British ambassador and associate of Steele’s. It was also known that a copy was passed to McCain and his associate, David Kramer.

What was not known was that McCain was provided a final copy of the dossier directly by Simpson, the former Wall Street Journal reporter who started Fusion GPS.

“Less than twenty-four hours later, Kramer returned to Washington. Next, Simpson shared a copy of the dossier confidentially with McCain.”

McCain’s spokeswoman did not respond to The Daily Caller’s request for comment.

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