Former national security adviser John Bolton was so disturbed by the efforts to get the Ukrainians to investigate President Donald Trump's political opponents that he called it a "drug deal," former White House official Fiona Hill reportedly told Congress on Monday.
Hill, the former top Europe expert in Trump's White House, testified that Bolton told her he wanted no part of the effort that involved acting White House chief of staff Mick Mulvaney, a person in the room for Hill's testimony told NBC News. Bolton also was said to have referred to Rudy Giuliani as a "hand grenade."
Giuliani has acknowledged in recent interviews that he had asked a Ukrainian prosecutor for information about former Vice President Joe Biden.
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The New York Times first reported details of Hill's testimony Monday night.
Bolton was fired by Trump in September.
Hill testified that Bolton told her to report the situation to the top lawyer at the National Security Council, John Eisenberg, according to the person in the room for Monday's closed-door hearing.
Hill told lawmakers she considered what was happening to be a clear counterintelligence risk to the United States, the individual in the room for Hill's testimony told NBC News.
Giuliani said that he was disappointed to learn about Bolton's reported comments.
"I always liked and respected John," the president's personal attorney said after hearing about the testimony. "I'm very disappointed that his bitterness drives him to attack a friend falsely and in a very personal way. It's really ironic that John Bolton is calling anyone else a hand grenade. When John is described by many as an atomic bomb."