Sen. Lindsey Graham (R-S.C.) warned Rudy Giuliani in an interview with The Daily Beast to make sure that the information he has gathered about President Trump's opponents in Ukraine isn't Russian propaganda.

“He has not shared any of that information with me. My advice to Giuliani would be to share what he got from Ukraine with the IC [intelligence community] to make sure it’s not Russia propaganda. I’m very suspicious of what the Russians are up to all over the world.”

Context: Giuliani traveled to Ukraine last month to meet with former Ukrainian prosecutors and other officials to investigate corruption allegations against Joe Biden, which he believes will undermine the case for impeachment.

President Trump's request in July that Ukrainian President Volodymyr Zelensky work with Giuliani to investigate Biden and allegations of Ukrainian interference in the 2016 election helped spark the impeachment inquiry.

Upon returning, Giuliani has said Trump wants him to brief the Justice Department and Republican senators about the information he gathered. In December, Graham invited Giuliani to testify before the Senate Judiciary Committee about his "concerns."

The big picture: Trump's former top Russia expert Fiona Hill and others in the intelligence community have warned that the allegations of Ukrainian interference are a "fictional narrative" propagated by Russian security services.

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