Papadopoulos, who is 30 years old, joined the Trump campaign in early March 2016 as a foreign adviser.
"Today's announcement has nothing to do with the President, has nothing to do with the President's campaign or campaign activity".
Sanders's assertion is at odds with the indictment issued by the Special Counsel investigation into Russian meddling in the 2016 election, which states Papadopoulos was encouraged to meet with Russian officials by campaign officials.
She also criticized Hillary Clinton's campaign and the Democratic National Committee for their contributions which funded research for a dossier alleging Mr. Trump's connections to Russian Federation.
Sanders emphasized that she's "not sure that the president recalls specific details" of a March 31 national security team meeting at Trump International Hotel in Washington, D.C.in which Papadopoulos was present.
"What Papadopoulos did was lie and that's on him, not the campaign", said Mrs. Sanders.
Speaking of Papadopoulos's role, she said: "It was extremely limited, it was a volunteer position".
Lawmakers from both sides of the aisle warned against calls to fire special prosecutor Robert Mueller or presidential pardons for those indicted.
When asked about that later in the briefing, Sanders insisted that it was only one meeting between Trump campaign officials and Russian officials, while trying to say that Clinton's campaign was actually involved in colluding with Russia.
"It has to do with his failure to tell the truth". "No activity was ever done in an official capacity on behalf of the campaign in that regard". Majority took place well before the campaign ever even existed.
As she spoke, CNN cited its report that Trump was "seething" behind the scenes after reports of the indictments on Monday, and noted that Trump has frequently tweeted about the probe.