Mr Banks, who was co-founder of the Leave.
Cambridge Analytica, which was hired by Trump in 2016, has denied its work on the US president's successful election campaign made use of allegedly improperly harvested data - but questions have since been raised over any role in other votes.
Now to another Brexit-related event: the appearance of the businessman who bankrolled the Leave.
Banks was attending the select committee inquiring into fake news, in the aftermath of the leak of a cache of emails belonging to him, Wigmore and others which suggested that his dealings with Russian Federation were far more extensive than previously thought.
The businessman sat alongside Leave.EU communications chief Andy Wigmore as they joined Nigel Farage for an exclusive LBC interview.
Banks said he and Wigmore had overstated the role of data and artificial intelligence in the campaign in part to reflect its "disruptive" nature and their role as underdogs.More news: NY attorney general sues Trump Foundation, alleges illegal self-dealing
The reports emails existed showing Banks discussed a potential business deal involving six Russian gold mines with ambassador Alexander Yakovenko after being introduced to him by a suspected Russian spy.
Brexiteer Arron Banks will face further questions from MPs after he admitted he "led people up the garden path" during the referendum campaign.
"It's been conflated from two witnesses that frankly, the credibility of them was shot to pieces", he said.
"This whole fake news narrative stated to roll from it".
The pair and Mr Farage have had a meeting with a senior official at the United States embassy over claims made against them, Mr Wigmore added. "You have a vested interest in trying to discredit the Brexit campaign". "If that's provocation or a lie, if you want to call it that, yeah".More news: McGregor Legal Situation "Not Too Serious", Says Experts; 2018 UFC Return Possible
"The only thing we gave in the second meeting was the telephone number of the transition team because the Russians wanted to get hold of the transition team", Banks said. He added that nothing substantive was discussed during the meetings and that the second lunch came after the two men had met Mr. Trump in NY in the wake of his election victory in November, 2016.
Asked about allegations he was reporting back to the Russians three days after meeting newly-elected Donald Trump, he said: "It's complete nonsense".
Mr Paisley posted a picture on Twitter of the quartet smiling for the camera on the House of Commons terrace, Mr Banks with cigarette in hand.
He added: "Where's the evidence we took Russian money". His three children are also dual citizens, he added.
The combative testimony comes at an awkward time for the government as it engages in last-gasp efforts to persuade wavering Conservative Party lawmakers not to rebel against its key Brexit legislation in votes on Tuesday and Wednesday. The law would incorporate all European Union laws into British laws, paving the way for the U.K.to pick and choose which laws to keep or amend.More news: Wendy's, Denny's and more trolling IHOP over burger announcement