WASHINGTON — Former national security adviser Michael Flynn denied to FBI agents in an interview last month that he had discussed U.S. sanctions against Russia with that country’s ambassador to the United States before President Donald Trump took office, contradicting the contents of intercepted communications collected by intelligence agencies, current and former U.S. officials said.

The Jan. 24 interview potentially puts Flynn in legal jeopardy. Lying to the FBI is a felony. But several officials said it is unclear whether prosecutors would bring a case, in part because Flynn may parse the definition of the word “sanctions.”

He also followed his denial to the FBI by saying he couldn’t recall all of the conversation, officials said.

Any decision to prosecute would lie with the Justice Department. A spokesman for Flynn had no response. The FBI and the Justice Department declined to comment.

Flynn spoke to Russian Ambassador Sergey Kislyak after Trump’s election and denied for weeks that the December conversation involved sanctions the Obama administration imposed on Russia in response to its purported meddling in the U.S. election. Flynn’s denial to the FBI was similar to what he had told Trump’s advisers, according to the officials who spoke on condition of anonymity.

In a recent interview with The Daily Caller, Flynn said he didn’t discuss “sanctions” but did discuss the Obama administration’s expulsion of 35 Russian diplomats it said were “intelligence operatives.” The move was part of the sanctions package announced Dec. 29.

Earlier, in an interview with the Washington Post, he denied discussing sanctions but later issued a statement saying “that while he had no recollection of discussing sanctions, he couldn’t be certain that the topic never came up.”

Trump asked for Flynn’s resignation Monday after published reports that Flynn had misled Vice President Mike Pence in denying the substance of the call and that Justice Department officials had warned the White House that Flynn was a possible target of Russian blackmail as a result.

Senior officials who have reviewed the phone call thought Flynn’s statements to Kislyak were inappropriate, if not illegal, because he suggested that the Kremlin could expect a reprieve from the sanctions.