Updated

The top White House spokesman staunchly defended President Trump’s handling of the controversy over former National Security Adviser Michael Flynn’s contact with the Russian ambassador – claiming the president acted swiftly to get to the bottom of those discussions, while rejecting suggestions Flynn may have violated the law.

White House Press Secretary Sean Spicer said Trump in the end sought Flynn’s resignation because of “trust” issues, not legal ones.

“He took immediate, decisive action,” Spicer said Tuesday, referring to Trump’s earlier decision to have the White House counsel review the allegations against Flynn last month.

The statements from Spicer come as Democrats and even a few Republicans step up calls for further investigation, in the wake of Flynn’s departure Monday night. House Democrats, moments before the White House briefing, continued to raise the possibility Flynn may have violated the Logan Act, a law meant to prevent private citizens from conducting U.S. diplomacy.

But Spicer, who was peppered with questions on the controversy Tuesday afternoon, maintained that a review from the White House counsel’s office determined there was "not an illegal issue."

Rather, Spicer said Trump’s issue with Flynn came down to concerns he had been “misleading” Vice President Pence and other officials about past contacts with the Russians.

“The issue, pure and simple, came down to a matter of trust,” Spicer said.

Flynn already has acknowledged he gave “incomplete” information to Pence about his past contact with the Russian ambassador. Concerns about Flynn’s honesty and recollection created what Spicer called a “critical mass and an unsustainable situation.”

Flynn, in an email to Fox News, said Monday night: "I have nothing to be ashamed for and everything to be proud of."

Spicer tried to tamp down the controversy Tuesday as Democrats showed little interest in letting go of the issue.

Rep. Elijah Cummings, D-Md., top Democrat on the House oversight committee, blasted his GOP counterparts for not pursuing an investigation.

“What did the president know and when did he know it?” Cummings told reporters.

Top intelligence committee Democratic Rep. Adam Schiff said, “The president, I think, owes the American people an explanation.”

A handful of Republicans indicated an interest in pursuing the matter further. Sen. Bob Corker, R-Tenn., chairman of the Senate Foreign Relations Committee, said “it would not be out of the question” for there to be hearings on the matter and for Flynn to testify.

On another front, congressional Republicans as well as the White House also are raising questions about how details of Flynn’s discussions leaked to the media in the first place.

The president, after accepting Flynn’s resignation overnight, tweeted Tuesday morning that, “The real story here is why are there so many illegal leaks coming out of Washington?”

Fox News first reported Monday night that House Intelligence Committee Chairman Devin Nunes, R-Calif., wants the FBI to conduct an assessment of recent media leaks.