David Jackson, and Kevin Johnson

USA TODAY

WASHINGTON — President Trump knew for more than two weeks that ex-national security adviser Michael Flynn lied about his contact with a Russian ambassador and demanded his resignation because he could no longer trust him, the White House spokesman said Tuesday.

"The evolving and eroding level of trust as a result of this situation, and a series of other questionable instances, is what led the president to ask for General Flynn's resignation," Trump spokesman Sean Spicer said.

Vice President Pence didn't know about Flynn's actions until Feb. 9, Pence's press secretary, Marc Lotter, told the Washington Post and NBC News Tuesday.

Flynn's resignation, less than a month after Trump took office, came as a growing number of members of Congress sought an investigation into Flynn's contacts with the Russians and those of the entire Trump White House, which has made improved ties between the two countries a cornerstone of the president's foreign policy.

Trump and aides spent weeks evaluating allegations against Flynn and concluded that he misled Pence and others when he said he had not discussed then-pending sanctions on Russia with the U.S. ambassador from that country, Spicer and other officials said.

Pence echoed Flynn's denials in a television interview, and protested Flynn's conduct in light of recent revelations.

Trump did not oust Flynn sooner, Spicer said during a White House news briefing, because there was no proof Flynn had broken the law by calling Russian ambassador Sergey Kislyak. Spicer said Trump did not authorize Flynn to call Kislyak about then-pending sanctions from the Obama administration against Russia over its involvement in the 2016 elections.

"It was not an issue of law, it was an issue of trust," Spicer said.

Members of Congress, including some Republicans, said Flynn's departure underscores concerns about the Trump administration, the Russians, and Russian President Vladimir Putin, potential ties that are already the subject of an FBI investigation.

Flynn's forced resignation "is a troubling indication of the dysfunction of the current national security apparatus" and "also raises further questions about the Trump administration’s intentions toward Vladimir Putin’s Russia," said Sen. John McCain, R-Ariz., chairman of the Senate Armed Services Committee.

McCain cited "statements by the president suggesting moral equivalence between the United States and Russia despite its invasion of Ukraine, annexation of Crimea, threats to our NATO allies, and attempted interference in American elections."

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Another prominent Republican, Sen. Lindsey Graham of South Carolina, told CNN: "Did General Flynn act alone? I want to know what Russia is up to."

Citing reports that the Justice Department warned the White House a month ago that Flynn was vulnerable to blackmail because he had misrepresented his talks with the Russian ambassador, Democrats and other Trump critics said they would continue to press Trump for a probe of the incident.

"The Trump administration has yet to be forthcoming about who was aware of Flynn's conversations with the ambassador and whether he was acting on the instructions of the president or any other officials, or with their knowledge," said Rep. Adam Schiff of California, ranking Democrat on the House Intelligence Committee.

For his part, Trump took to social media to protest news leaks.

While not mentioning Flynn, Trump tweeted: "The real story here is why are there so many illegal leaks coming out of Washington? Will these leaks be happening as I deal on N.Korea etc?"

Trump declined to answer reporters' questions about Flynn during a Tuesday morning meeting of parents and teachers.

Calling Sergey

Flynn's departure, the first high-profile resignation of the Trump administration, started with a phone call.

During a conversation late last year with Kislyak,Flynn discussed then forthcoming sanctions the Obama administration was placing on Russia over involvement in the U.S. election, including the hacking the emails of Democratic Party officials close to nominee Hillary Clinton.

Flynn initially denied discussing sanctions with Kislyak — a falsehood repeated in public statements by Vice President Pence, among other administration officials. Aides to the president said Pence protested and played a role in discussions about what to do with Flynn.

"Misleading the vice president really was the key here," presidential counselor Kellyanne Conway told NBC's Today show Tuesday.

The content of Flynn’s conversations with the Russian ambassador and a discussion of sanctions emerged during the FBI’s ongoing investigation into communications between former and current Trump aides and Russian government officials, a U.S. official said.

Sally Yates, then-acting attorney general during the Trump administration transition, was prompted to alert the White House counsel, Don McGahn, Spicer said. Other officials, including Vice President Pence, said they were assured that Flynn’s pre-inaugural conversations did not include the subject of sanctions against Russia, said the official who spoke on condition of anonymity because officials were not authorized to comment on the matter publicly.

Fearing that the content of conversations could later be used against Flynn by Russian authorities as a form of blackmail, the official said the decision was made to raise the matter with the White House.

It was immediately unclear how the White House responded to Yates’ information, the official said.

Yates, a holdover from the Obama administration, was later fired by Trump for refusing to defend the president’s controversial executive order to suspend immigration from seven Muslim-majority countries. That order, now the subject of multiple court challenges across the country, is on hold.

The official with knowledge of the matter said the federal inquiry continues into the communications with Russian officials, though it was not clear what affect, if any, Flynn’s resignation would have on the investigation.

Shortly before acting Yates alerted the White House of inconsistencies in Flynn's public statements about his private conversations with the Russian ambassador to the U.S.— secretly monitored by federal authorities — FBI agents interviewed the then-Trump administration national security adviser, the official said.

The official declined to elaborate on the contents of the interview, but indicated that Yates moved to raise concerns with the White House counsel about Flynn's possible exposure to blackmail by Russian authorities within a day or two after the interview.

The official declined to comment on whether authorities had concluded that Flynn's statements were truthful.

Lying to the FBI is a felony offense.

At the White House, Spicer said Trump learned of the Justice Department's concerns on Jan. 26 and immediately asked McGahn's office to investigate. While there is no evidence Flynn broke the law, Spicer said Trump believes his now-former national security adviser misled Pence and others about the phone call. Spicer said Trump requested the resignation, though other administration officials have told reporters that Flynn acted voluntarily.

While Trump named an acting national security adviser — retired three-star general Joseph Keith Kellogg Jr. — the White House has floated other names to take over the post full time.

They include Robert Harward, a former deputy commander of U.S. Central Command and protégé of Defense Secretary Jim Mattis, and retired general David Petraeus, a former CIA director who resigned after acknowledging he gave classified information to a biographer with whom he was having an affair.

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Full text of Michael Flynn's resignation letter

In his resignation letter, Flynn said that, because of the "fast pace of events," he "inadvertently" gave Pence and others "incomplete information" about his call with the Russian ambassador. "I have sincerely apologized to the President and the Vice President, and they have accepted my apology," Flynn wrote.

While a close adviser to Trump during his presidential campaign, Flynn was in trouble from Day One. Critics cited his past ties to Russia, and what appeared to be signs of disorganization within the National Security Council.

Flynn, who had been fired as head of the Defense Intelligence Agency by President Obama, made himself a political target by campaigning aggressively against Clinton, sometimes leading Trump supporters in chants of "lock her up!"

Flynn resigned hours after Spicer announced that the president was "evaluating the situation" regarding Flynn.

Flynn's tenure as national security adviser, less than a month, is by far the shortest ever for the influential position. President Ronald Reagan's first national security adviser, Richard Allen, lasted just under a year.

Clinton, whom Trump defeated in the November election, also weighed in on Flynn, retweeting a message from former spokesman Philippe Reines about the involvement of Flynn and his son, Michael Flynn Jr., spreading "fake news" about the Democratic campaign.

"Philippe's got his own way of saying things, but he has a point about the real consequences of fake news," Clinton said.