It was not clear how frequently the group, which included former Pentagon officials, held discussions with other prominent Russians thought to be close to the Kremlin, NBC News reported.
"The Biden administration did not sanction those discussions," a State Department spokesperson said in response to questions from Reuters.
"And as we've said repeatedly, nothing about Ukraine without Ukraine."
The spokesperson was referring to an administration policy of not discussing possible negotiations on ending the war without involving Ukrainian officials.
White House national security spokesperson John Kirby said in an interview with CBS News that the White House was aware of the unofficial discussions.
Persons:
Joe Biden's, Sergei Lavrov, Lavrov, Richard Haass, Biden, we've, John Kirby, Jonathan Landay, Simon Lewis, Eric Beech, David Gregorio Our
Organizations:
U.S, Russian, White House and State Department, NBC News, Foreign Relations, White, Pentagon, Kremlin, State Department, Reuters, House, CBS News, NBC, Thomson
Locations:
Ukraine, New York, U.S, Russia