The FBI on Wednesday made its first statement on the accuracy of a four-page memo that allegedly depicts anti-Trump bias at the agency.

The document reportedly accuses the FBI and US Justice Department of abusing their surveillance powers by running a secret eavesdropping operation against Carter Page, an adviser to US President Donald Trump during the 2016 election.

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"As expressed during our initial review, we have grave concerns about material omissions of fact that fundamentally impact the memo's accuracy," the FBI said in its short statement. Justice Department officials have said releasing the memo could jeopardize classified information.

Democrats claim the memo — compiled by House Intelligence Committee Chairman Devin Nunes — is an attempt to discredit the FBI-led investigation into alleged collusion between the Trump campaign and Russian officials.

The memo was distilled from a larger volume of documents used by the FBI to get a national security warrant to spy on Page, who was suspected of espionage.

US media, citing lawmakers who have seen the document, reported that it alleges the FBI's warrant was obtained by submitting evidence from the contentious and unproven "Russia dossier" compiled by former British intelligence agent Christopher Steele.

The House committee voted on Monday to release the memo, although Nunes still needs the president's approval. Trump has until the weekend to decide whether or not to declassify the information for public release.

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Declassification imminent

The FBI statement came a day after Trump was overheard telling a congressman that he "100 percent" supported the memo's release, and hours after White House Chief of Staff John Kelly said he expected the memo's release to be "pretty quick."

Nunes, a close ally of the president, said in a statement on Wednesday that objections to the memo's release were "spurious."

White House chief of staff John Kelly said during an interview with Fox News Radio on Wednesday that the president "wants everything out so the American people can make up their own minds and if there are people to be held accountable, then so be it."

There are concerns the memo could be used to discredit special counsel Robert Mueller, the former FBI director who is leading the investigation into alleged Russian meddling in the 2016 presidential election, an investigation that appears to be edging ever closer to Trump himself.

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dv, dm/jm (AP, Reuters)