U.S. media reports say White House national security adviser Michael Flynn privately discussed U.S. sanctions against Russia with Moscow's ambassador to the United States during the month before President Donald Trump took office.
The reports on February 9 in The Washington Post and The New York Times cite unnamed current and former U.S. officials.
The Washington Post said some senior U.S. officials interpreted the contacts as a "potentially illegal" signal to Russia that it could expect a reprieve from sanctions imposed by the Obama administration in December.
Trump advisers have said that Flynn spoke to Sergei Kislyak a few days after Christmas merely to arrange a phone call between Trump and Russian President Vladimir Putin after the inauguration.
But The New York Times report cites current and former U.S. officials as saying that conversation -- which it says took place the day before Obama imposed sanctions on Russia over alleged interference in the U.S. election -- went far beyond discussion of a postinauguration phone call.
According to The New York Times, the officials said that Flynn never explicitly promised relief from sanctions but appeared to give the impression it would be possible.
The New York Times says the accounts of the conversations raise the prospect that Flynn violated a law against private citizens engaging in diplomacy, and directly contradict statements made by Trump advisers.
Flynn initially denied that he had discussed sanctions with Kislyak. Asked in a February 8 interview whether he had ever done so, he twice said, "No."
But on February 9, a spokesman for Flynn said that Flynn "indicated that while he had no recollection of discussing sanctions, he couldn’t be certain that the topic never came up."