Top Democrats call for Flynn's suspension over allegations he talked sanctions with Russian envoy Flynn discussed sanctions with Russia's U.S. envoyahead of Trump's inauguration.

 -- At least two Democrats on the House Intelligence Committee are calling for President Donald Trump's national security adviser, Michael Flynn, to be suspended in the wake of allegations that he discussed the U.S. sanctions against Russia in a conversation with Moscow's ambassador to the U.S. ahead of Trump’s inauguration.

The allegations raise "serious questions of legality and fitness for office," the top Democrat on the committee, Rep. Adam Schiff of California, said in a statement today. If the allegations are proven true, Flynn "should no longer serve in this administration or any other."

Another top Democrat, Rep. Eric Swalwell, also of California, said Flynn should step aside while the allegations are looked into.

"The White House should immediately SUSPEND National Security Advisor Flynn & REVOKE access to classified information until investigated," Swalwell said in a statement online.

ABC News has confirmed that in the weeks before the inauguration, Flynn discussed the sanctions issue with Russian Ambassador Sergey Kislyak.

Current and former U.S. officials familiar with the discussions were not able to say that Flynn made explicit promises to lift sanctions, but say the issue was discussed in the context that the incoming administration would have a chance to review them.

The fact that sanctions were discussed at all –- which was first reported by The Washington Post on Thursday -– raises legal questions about private citizens engaging in diplomacy that could undermine the intent of a sitting president. It also conflicts with repeated denials by Flynn and other senior members of the Trump administration that Flynn had discussed the sanctions issue during the calls.

U.S. authorities continue to investigate communications between Flynn and Russian officials, but have yet to find any clear evidence of wrongdoing.

When news of the contacts between Flynn and the Russian envoy first broke in January -- revealing that the two spoke around the time that President Obama issued new sanction against Russia in response to its alleged cyberhacking to interfere with the U.S. election -- the White House said the contacts were only focused on arranging a phone call between Russian President Vladimir Putin and then-President-elect Trump. "They exchanged logistical information on how to initiate and schedule that call," Trump’s spokesman Sean Spicer said at the time. "That was it. Plain and simple."

Spicer later told ABC News the phone call covered a number of topics, including the crash of a Russian military plane carrying an army choir on Christmas day, holiday greetings, and an invitation from the Russian government for the Trump administration to attend upcoming Syrian peace talks. He emphasized that the topic of U.S. sanctions against Russia did not come up during the conversation.

Spicer also told reporters at the time that Flynn and the Russian ambassador talked by phone on Dec. 28, but later told ABC News he misspoke and the call was on Dec. 29, the same day that President Obama expelled 35 Russian diplomats from the U.S. and closed a handful of Russian diplomatic facilities as punishment for the alleged Kremlin meddling.

In an interview in January, Vice President Mike Pence also weighed in, telling CBS News that “They did not discuss anything having to do with the United States’ decision to expel diplomats or impose censure against Russia.” A senior administration official told ABC News that Pence's information on the case had come from speaking with Flynn directly.

As recently as this week Flynn denied discussing sanctions with the Russian ambassador. But today the White House appeared to be moving back from the denial: a senior administration official told ABC News that Flynn doesn’t recall any discussion of sanctions ever coming up with Kislyak, but “isn’t completely certain.”

Russian President Vladimir Putin’s spokesman, Dmitry Peskov, confirmed that Flynn spoke by phone with Russia's Washington ambassador, Sergey Kislyak, but said reports that they had discussed sanctions were "wrong."

The administration’s contacts with Russia are under scrutiny after U.S. intelligence concluded that the Kremlin had intervened in the elections to help Trump and harm his Democrat opponent, Hillary Clinton. A declassified report from the Director of National Intelligence in December found Russia had used cyberattacks and propaganda to try to undermine American democracy and to tilt the balance in favor of Trump. A broad Senate investigation is currently underway into the alleged interference.