Updated at 9:59 a.m. ET Feb. 14
President Trump's national security adviser Michael Flynn resigned late Monday night amid allegations he inappropriately talked about U.S. sanctions with a Russian official, and later allegedly misled then-Vice President-elect Pence about the conversations. Flynn spoke with the Russian ambassador in December, before Trump was inaugurated.
Flynn issued a statement through the White House Monday evening that said he had made numerous phone calls with foreign officials to facilitate the transition, and made a mistake in what he told Pence:
"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. I have sincerely apologized to the President and the Vice President, and they have accepted my apology."
Trump has named an acting national security adviser, retired Lt. Gen. Joseph Kellogg.
Almost immediately upon Flynn's resignation, names began to surface of potential replacements. The leading contender is retired Vice Adm. Robert S. Harward, a former U.S. Navy SEAL who once worked for the National Security Council and now works as an executive for Lockheed Martin. Other contenders are Kellogg, who has been temporarily elevated from the position of chief of staff in the National Security Council and who is vying to keep the top security spot permanently.
Former CIA Director and retired Gen. David Petraeus is also in the mix. Petraeus fell from grace during the Obama administration after he was accused of sharing classified information with a woman who was his biographer and with whom he was also having an extramarital affair.
In the wake of Flynn's exit from the new administration, lawmakers in Russia sought to defend him and said his absence from the White House would damage relations with the Kremlin, the Washington Post reported early Tuesday.
Flynn's near-midnight resignation capped a confusing evening in which the White House sent mixed signals about the embattled presidential adviser's fate.
White House press secretary Sean Spicer had said the White House was "evaluating the situation" when it comes to Flynn.
But, just an hour earlier, a senior Trump adviser, Kellyanne Conway, said on MSNBC that the president continued to have "full confidence" in Flynn.
Notably, however, Trump declined to express that same sentiment. When asked by White House reporters in a scrum in the West Wing if he had "full confidence" in Flynn, Trump deferred to a statement to come. (Trump did, however, express full confidence in Chief of Staff Reince Priebus. "Reince is doing a great job," Trump said. "Not a good job. A great job.")
"Look at the statement, look at the statement," Trump said.
Spicer was asked if he had the statement and read it:
"The president is evaluating the situation. He's speaking to the vice president — to Vice President Pence, relative to the conversation the vice president had with Gen. Flynn and also speaking to various other people about what he considers the single most important subject there is, our national security."
The comments and confusion come after days of speculation that Flynn could be on the outs given that he may have lied to or misled Mike Pence when Pence was vice president-elect. Flynn has denied that he talked to the Russian ambassador about sanctions President Obama leveled back in December. Pence went on Sunday shows and echoed what Flynn told him.
But Flynn backed away from the comments. Through a spokesman, he told the Washington Post "that while he had no recollection of discussing sanctions, he couldn't be certain that the topic never came up."
Spicer told NPR a month ago that it was "doubtful" Flynn and the Russian ambassador talked about the sanctions, because that's what Flynn told him. But he left open the possibility that they could have talked about the sanctions.
So it's possible that Flynn may have misled both the incoming vice president and press secretary about the extent of his discussions with the Russian ambassador.
Flynn has also already been the subject of accusations of mismanagement at the National Security Council. The New York Times reported over the weekend on the NSC, painting a "chaotic" scene:
"Officials said that the absence of an orderly flow of council documents, ultimately the responsibility of Mr. Flynn, explained why [Secretary of Defense James] Mattis and Mike Pompeo, the director of the C.I.A., never saw a number of Mr. Trump's executive orders before they were issued. One order had to be amended after it was made public, to reassure Mr. Pompeo that he had a regular seat on the council.
"White House officials say that was a blunder, and that the process of reviewing executive orders has been straightened out by Reince Priebus, the White House chief of staff."
With Flynn now gone, it remains to be seen whether and how the Trump administration can bring some order to the NSC — and what the broader implications of the early staff shakeup may be both politically and in terms of national security.
NPR's Arnie Seipel contributed to this post.