California Rep. Adam Schiff claimed Wednesday that Republicans on the House Intelligence Committee altered a controversial surveillance memo after the panel voted earlier this week to release the document to the public.

In a letter to California Rep. Devin Nunes, the chairman of the committee, Schiff claimed that Democrats discovered on Wednesday that the classified four-page memo had been “secretly altered” prior to being sent to the White House for review.

“After reviewing both versions, it is clear that the Majority made material changes to the version it sent to the White House, which Committee members were never apprised of, never had the opportunity to review, and never approved,” Schiff wrote.

The Intelligence Committee voted along party lines on Monday to release the memo, which alleges that the FBI and Justice Department misled a federal judge in order to obtain a surveillance warrant in order to spy on Trump associates.

The White House is poised to release the memo on Thursday.

Schiff did not say what edits were made to the memo, and a spokesman for the House Intelligence Committee called the Democrat’s effort a “strange attempt to thwart publication of the memo.”

In a statement to The Daily Caller, Jack Langer said that “minor edits” including “grammatical fixes” were made to the document.

“Two edits [were] requested by the FBI and by the Minority themselves,” Langer said.

The edits were requested by the FBI after Sunday, when FBI Director Christopher Wray met with Nunes to review the memo.

Schiff is calling on Nunes to withdraw the memo and hold another vote next week on whether to release the document. He suggested in the letter that the committee could also vote on whether to release a 10-page memo that Democrats crafted as a response to the Nunes document.

“It is now imperative that the Committee Majority immediately withdraw the document that it sent to the White House,” says Schiff.

“This is deeply troubling, because it means that the Committee Majority transmitted to the White House an altered version of its classified document that is materially different than the version on which the Committee voted,” he added.

Earlier on Wednesday, the FBI released a rare on-the-record statement expressing “grave concerns” with what the bureau claims are “material omissions of fact” from the memo. On Sunday, FBI Director Christopher Wray met with Nunes to review the document. (RELATED: FBI Makes Last-Ditch Effort To Block Release Of Spy Memo)

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