Senator Mark Warner, the top Democrat on the Senate Intelligence Committee, warned Republicans Friday that unmasking an FBI mole who fed information to the Russia probe would be “potentially illegally.”

"It would be at best irresponsible, and at worst potentially illegal, for members of Congress to use their positions to learn the identity of an FBI source for the purpose of undermining the ongoing investigation into Russian interference in our election," said Warner.

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"Anyone who is entrusted with our nation’s highest secrets should act with the gravity and seriousness of purpose that knowledge deserves," he added.

The warning comes after Republican allies of President Donald Trump seized on a report that an FBI informant provided information to investigators probing allegations of collusion between the Trump campaign and Russia.

The New York Times reported Wednesday that the informant met top Trump aides including Carter Page and George Papadopoulos, Trump campaign foreign policy officials who also met with Russian government-linked contacts during the 2016 presidential campaign.

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The president alleged that the Obama administration was behind a plot to implant the informant, describing the revelation as “bigger than Watergate.” U.S. officials have told CNN that the informant was not implanted in the Trump campaign.

The FBI is reportedly working to limit the fallout from the revelation, with the Washington Post reporting Thursday that the congressional GOP was determined to expose the identity of the mole.

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Intelligence officials told the publication that the agency is battling to limit the impact on other investigations the source has taken part in if the person's identity is exposed.

This article was first written by Newsweek

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