Former national security adviser Michael Flynn exits a vehicle as he arrives for his sentencing hearing at U.S. District Court in Washington, U.S., December 18, 2018. REUTERS/Jonathan Ernst

WASHINGTON (Reuters) - President Donald Trump’s former national security adviser Michael Flynn said on Tuesday he knew lying to the FBI was a crime as he stood by his guilty plea in a case stemming from the investigation into possible collusion between Trump’s 2016 campaign and Russia.

Flynn pleaded guilty in December 2017 to lying to FBI agents about his conversations with Sergei Kislyak, Russia ambassador in Washington at the time.

In a filing with the court, a lawyer for Flynn had noted that he was not warned during an FBI interview that lying would be a crime, but an attorney for Flynn told the court on Tuesday during a sentencing hearing that the retired lieutenant general was not entrapped.

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