He's out. Trump national security adviser Michael T. Flynn resigned Monday night after revelations he misled VP Mike Pence and other senior White House officials about his conversations with Russia's ambassador to the United States.

National Security Adviser

Michael T. Flynn, Sashay Away. pic.twitter.com/7fsj0SRAqM — RuPaul (@RuPaul) February 14, 2017

Before his resignation letter was released, the Washington Post reported that the administration had been warned for weeks that Flynn was considered a potential Russia blackmail risk.

The White House says tonight that the acting national security adviser (in other words, not his replacement, but a temporary person to fill the post) will be retired Lt. General Joseph Keith Kellogg, Jr., a Vietnam War veteran.

Change in Headline pic.twitter.com/lTtxMHE4zW — Editing TheGrayLady (@nyt_diff) February 14, 2017

From the New York Times report tonight:

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 Mr. Trump's inauguration. Mr. Flynn previously had denied that he had any substantive conversations with Ambassador Sergey I. 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 Mr. Flynn had not been fully forthright about his conversations with the ambassador. As a result, the Justice Department feared that Mr. Flynn could be vulnerable to blackmail by Moscow. In his resignation letter, which the White House emailed to reporters, Mr. 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."

Andrea @mitchellreports gets to the heart of the matter: Did Flynn talk sanctions w/Russia on the order or approval of Trump—or anyone else? pic.twitter.com/y8b2bQDTJZ — Bradd Jaffy (@BraddJaffy) February 14, 2017

Worth noting that Gen. Flynn now leaves two administrations, from both political parties, in disgrace. — Brian Taff (@briantaff6abc) February 14, 2017

You can imagine North Korea is all "We launched a missile, and the US National Security Advisor resigned! SAY WHAT?" — James Ledbetter (@jledbetter) February 14, 2017

Worth reminding: #MikeFlynn saying 1.7 billion Muslims have a cancer & needs to be "excised", didn't prevent him from becoming NSA to #Trump — Bahman Kalbasi (@BahmanKalbasi) February 14, 2017

Not credible that Trump didn't know that Flynn had spoken about sanctions with the Russian Amb; as if Flynn could free lance on this alone.. — Nouriel Roubini (@Nouriel) February 14, 2017

.@MajorCBS says Petraeus meeting at WH will be later this week. https://t.co/UnNq9I3Bxv — margaret brennan (@margbrennan) February 14, 2017

Flynn out. Lt. Gen. Keith Kellog named "acting" National Security Adviser. Kellog was part of transition and well-known to @POTUS — Major Garrett (@MajorCBS) February 14, 2017

Mandy, Season 1 of the West Wing https://t.co/5P8GBApcs3 — Sopan Deb (@SopanDeb) February 14, 2017

Very interesting— K.T. McFarland, the Deputy Nat'l Security Adviser, was *not* named Acting NSA tonight. — Kyle Griffin (@kylegriffin1) February 14, 2017

Now we know that there is 1 person in America to whom WH officials are not allowed to lie: Mike Flynn. The other 320 mln are not so lucky — masha gessen (@mashagessen) February 14, 2017

Lol oh sure "to end the controversy." https://t.co/IsYS6X9pl3 — Ana Marie Cox (@anamariecox) February 14, 2017

Sen Schumer said earlier today Flynn's security clearance should be withdrawn until an "independent investigation" was completed on him –> pic.twitter.com/zsVQDEVCEY — Frank Thorp V (@frankthorp) February 14, 2017

Somehow I feel like rewatching "The Manchurian Candidate" & "From Russia With Love". — Clyde Haberman (@ClydeHaberman) February 14, 2017

.@MikePenceVP — the quiet/nice one — has now played a central role in the 2 biggest ousters of Trump, post-election: Christie and Flynn. — Glenn Thrush (@GlennThrush) February 14, 2017