National security adviser to the American President, Michael Flynn, resigned on Monday night after it was revealed that he had misled Vice President Mike Pence and other top White House officials about his conversations with the Russian ambassador to the United States.
Mr. Flynn, who served in the job for less than a month, said he had given “incomplete information” to about a telephone call he had with the ambassador in late December about American sanctions against Russia, weeks before Donald Trump’s inauguration as President.
He previously had denied that he had any substantive conversations with Ambassador Sergey Kislyak, and Mr. Pence repeated that claim in television as recently as earlier this month.
But on Monday, a former administration official said the Justice Department last month warned the White House that Flynn had not been fully forthright about his conversations with the ambassador.
As a result, the Justice Department feared that he could be vulnerable to blackmail by Moscow.
In his resignation letter, which the White House emailed to reporters, Flynn said he had held numerous calls with foreign officials during the transition.
“Unfortunately, because of the fast pace of events, I inadvertently briefed the Vice President Elect and others with incomplete information regarding my phone calls with the Russian Ambassador,” he wrote.
“I have sincerely apologized to the President and the Vice President, and they have accepted my apology.”
The White House said in the statement that it was replacing Flynn with retired Lt. General Joseph Keith Kellogg, Jr., a Vietnam War veteran, as acting national security adviser.
