Michael Flynn reportedly spoke with Russia's ambassador to the US, Sergey Kislyak, about sanctions before President Donald Trump was sworn in, former officials who have reviewed transcripts of the conversations told The Washington Post and The New York Times. Lamar Salter Reports that President Donald Trump's national security adviser secretly called Russia's ambassador to the US to discuss sanctions before Trump took office raise "serious questions of legality and fitness for office," the House Intelligence Committee's top Democrat said Friday.

The Washington Post and the New York Times reported on Thursday night, citing nearly a dozen current and former officials in total, that the adviser, Michael Flynn, had spoken with Russia's ambassador to the US, Sergey Kislyak, about sanctions before Trump was sworn in — including at least one call on the day President Barack Obama imposed new penalties on Russia for its election-related meddling.

"The allegation that General Flynn, while President Obama was still in office, secretly discussed with Russia's ambassador ways to undermine the sanctions levied against Russia for its interference in the Presidential election on Donald Trump's behalf, raises serious questions of legality and fitness for office," Rep. Adam Schiff, the ranking member on the committee, wrote in a statement.

"If he did so, and then he and other Administration officials misled the American people, his conduct would be all the more pernicious, and he should no longer serve in this Administration or any other," Schiff added.

Rep. Eliot Engel, ranking member of the House Foreign Affairs Committee, echoed Schiff's calls for Flynn to step down.

"It's clear that concerns about General Flynn's ties to Russia were well warranted," Engel said in a statement on Friday afternoon. "If General Flynn negotiated with Russia to change American policy, he may be in violation of the Logan act, which bars such conduct. The President must relieve General Flynn immediately."

The Logan Act prohibits private citizens from engaging in diplomacy on behalf of the United States, but it is unclear if that would extend to a president-elect's transition team, Steve Vladeck, a professor at the University of Texas School of Law, noted last month.

Trump joined by Chief of Staff Reince Priebus, Vice President Mike Pence, senior adviser Steve Bannon, communications director Sean Spicer, and Flynn. REUTERS/Jonathan Ernst Still, Rep. Elijah Cummings, a ranking member of the House Oversight Committee, questioned "whether or not [Flynn] should have a security clearance."

“I am very concerned about General Flynn," Cummings told MSNBC on Friday. "His story has changed about three or four times. When you're not truthful, and then the vice president of the United States goes out there and says you didn't do anything wrong, and then, come to find out, that was not accurate, that's a major problem.”

Both Flynn and Vice President Mike Pence had previously denied that the sanctions were discussed on the calls, but counterintelligence officials told The Times they had transcripts of the conversations. Flynn denied the allegations through Wednesday, according to The Post, but then backed away from those denials through his spokesperson on Thursday.

Flynn, the spokesperson said, "indicated that while he had no recollection of discussing sanctions, he couldn't be certain that the topic never came up."

The former officials told The Post and The Times that while Flynn did not make any explicit promises about lifting the sanctions on Russia, Kislyak, the Russian ambassador, "was left with the impression that the sanctions would be revisited at a later time."

MSNBC reported on Friday that the White House had confirmed Flynn and Kislyak did discuss the sanctions in at least one of their conversations.

"The Administration has been misleading the public about this situation," Engel said. "Either General Flynn lied to the Administration or the Administration lied to the American people."

A paid speech in Moscow, and dinner with Putin

Federal officials who have read the transcript of the call "were surprised by Mr. Flynn's comments, since he would have known that American eavesdroppers closely monitor such calls," The Times reported. "They were even more surprised that Mr. Trump's team publicly denied that the topics of conversation included sanctions."

Schiff is one of seven top Democratic lawmakers calling on the Defense Department to investigate whether Flynn ran afoul of the Constitution by being paid to speak at a gala in Moscow in December 2015 celebrating the 10th anniversary of the state-sponsored news agency Russia Today.

In this file photo taken on Thursday, Dec. 10, 2015, Russian President Vladimir Putin, center right, with retired U.S. Lt. Gen. Michael T. Flynn, center left, and Serbian filmmaker Emir Kusturica, obscured second right, attend an exhibition marking the 10th anniversary of RT (Russia Today) 24-hour English-language TV news channel in Moscow, Russia. Mikhail Klimentyev/Sputnik, Kremlin Pool Photo via AP

"Since his retirement in 2014, General Flynn has made regular appearances on Russia Today (RT), that country's state-sponsored propaganda outlet," the lawmakers wrote. "He has admitted to being paid on at least one of these occasions — at an RT gala in Moscow where he dined with Russian President Vladimir Putin."

Flynn told The Washington Post last year that he had been paid to speak at the event, but he did not disclose the amount.

The emoluments clause of the Constitution deals with conflicts of interest that might arise by accepting gifts or payments from a foreign country. It has been cited by critics of Trump's refusal to sell off his businesses, which operate in four continents and nearly two dozen countries.

The lawmakers, in a letter to Defense Secretary Jim Mattis, requested that Mattis provide "all documents in the possession or control" of the Defense Department relating to Flynn's communications with Russian government officials, interactions with RT officials, and payments received from "any foreign source" from the time he retired through January 20 — the date on which Trump was inaugurated.