WATCH: MSNBC panel annihilates former Pence aide for 'peddling propaganda' about Papadopoulos

Marc Lotter, Vice President Mike Pence's old press secretary, may have left the Trump administration in September -- but that hasn't stopped him for stumping for his old employer.

In a panel discussion on MSNBC's Deadline: White House, Lotter said the White House is unconcerned with revelations from one-time campaign adviser George Papadopoulos whose guilty plea continues to make headlines this week.

Lotter claimed in the beginning of the discussion that Papadopoulos "didn't come up" when he was at the White House on Tuesday night, and said there are "no concerns" about people wearing wires despite widespread speculation that the former adviser had been wearing one as part of his cooperation with Mueller.

"This is a 30-year-old kid...trying to build a portfolio for himself," he claimed, echoing the Trump and his supporters' claims that Papadopoulos was incidental to the campaign. "At the end of the day, the only collusion we have in the campaign with Russians is the Clintons."

Naturally, both Wallace and anti-Trump GOP strategist Steve Schmidt took issue with Lotter's insistence that there's "no evidence of collusion" between Russian operatives and the Trump campaign. Schmidt, in particular, noted that people in and close to the Trump White House appear affronted when asked about the potential for collusion.

"Every single person around this administration, when asked a direct question about contacts with the Russians on this issue, has lied about it, 100 percent of the time, and the lie has unraveled," Schmidt said. 

After Lotter then pivoted to the GOP's inquisition into Hillary Clinton's alleged funding of the infamous "golden showers" dossier, all hell broke loose.

"We appreciate that you come here and speak on behalf of Donald Trump but why can't you say that we don't know -- we know there was attempted collusion. if it's not a crime, why are you so defensive about it?" Wallace asked the former vice presidential press secretary. When he said he's "not being defensive," Wallace said he looks like he's "about to jump through the camera and punch Steve Schmidt."

"I'll send an e-mail to friends at Fox and you can peddle your propaganda there," Wallace quipped. "Are you aware of anybody, as anybody who covers the White House is, that is concerned of what Papadopoulos has shared since he plead guilty in July?"

After a back-and-forth, Wallace appeared to lose her temper.

"I asked you if anybody was worried about their own legal liability, yes or no," she said. "I'm determining whether or not you're going to come on this show and tell the truth or lie."

Watch the entire exchange below, via MSNBC.

Part 1:

Part 2: