The infamous Steele dossier has left “a cloud” hanging over the Trump administration, even though it remains largely unverified, the top Democrat on the Senate Intelligence Committee said in a new interview.

Speaking to Politico’s Susan Glasser, Virginia Sen. Mark Warner said that more than a year after the publication of the dossier, “so little” of the document “has been fully proven, or conversely, disproven.”

“That’s pretty amazing,” said Warner, who serves as vice chairman on the Senate Intel panel.

“In my mind, one of the most amazing things is whether Mr. Trump or his campaign colluded or not, the fact that there is this explosive dossier that’s been in the public realm for a year-plus, and whether enormous scrutiny from the press or for that matter the work of the American government that so little of that dossier has been fully proven, or conversely, disproven, that’s pretty amazing.”

“As long as that sits out there, there’s going to be a cloud that hangs over this administration,” he added.

Warner’s committee is one of three congressional panels investigating Russian meddling in the presidential campaign and possible collusion between the Trump campaign and Russian operatives.

The dossier, which was written by former British spy Christopher Steele and funded by the Clinton campaign and DNC, is central to those collusion allegations.

But Warner’s comments show that congressional investigators are still in the dark about whether the allegations in the document are true.

The Senate Intel Committee has interviewed some witnesses familiar with the dossier, including Glenn Simpson, the founder of the opposition research firm that hired Steele to investigate Trump. The committee has also sought an interview with Steele himself, though as of October, that interview had not taken place.

In an October press conference, North Carolina Sen. Richard Burr, the Republican chairman of the Intelligence Committee, said that the committee’s investigation had “hit a wall” regarding the dossier.

“The committee cannot really decide the credibility of the dossier without understanding things like who paid for it, who are your sources and sub-sources,” Burr said in a press conference. (RELATED: Richard Burr: Senate Panel Has ‘Hit A Wall’ With Dossier)

And the veracity of the Steele report is a key question at the center of a debate over a four-page memo set to be released by the House Intelligence Committee which alleges abuses of the Foreign Intelligence Surveillance Act to obtain a spy warrant against former Trump campaign adviser Carter Page. (RELATED: Rod Rosenstein Renewed Spy Warrant Against Carter Page)

The FBI and Justice Department reportedly used the unverified dossier to obtain a warrant against Page in September 2016, just after he left the Trump campaign. The New York Times reported Sunday that Deputy Attorney General Rod Rosenstein renewed the warrant shortly after taking office last April.

The dossier alleges that Page was the Trump campaign’s Kremlin liaison, a charge which he has vehemently denied.

Congressional Republicans have questioned why U.S. officials obtained a surveillance warrant against Page if they had not verified the dossier.

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