Kopparberg, Ikea, Grolsch and Nivea are among the brands that have pulled or suspended adverts from GB News, with several brands saying they did not know their ads were due to appear on the channel. Their actions follow a campaign by the online group Stop Funding Hate (SFH).
Some commentators have described GB News as the UK's answer to Fox News, with a radical right-wing, hateful agenda.
But speaking to camera on GB News' Media Watch segment last night, Neil said: "Not a single example of hate has been given in evidence to justify the boycott of this channel."
He said it's "quite remarkable" that "serious executives in well-established companies can be so easily cowed" by Stop Funding Hate: "Woke nonsense has reached the boardroom and corporate capitalism is becoming the useful idiot of bigots bent on censorship."
He said that in some cases ad agencies were responsible for pulling adverts, and urged the brands involved to "have a word" with their agencies.
Neil said the boycott can "work both ways", with GB News viewers "incensed" with advertisers that have "taken against us for no reason". He invited brands and agencies with concerns about the channel to discuss them on air: "Our studio door is open."
"Not a single example of hate has been given in evidence for this boycott, so this programme offers a standing invitation to the boss of any company that thinks to the contrary... our studio door is always open."— GB News (@GBNEWS) June 17, 2021
Andrew Neil's message to companies choosing to boycott GB News. pic.twitter.com/Zo8rXYnNak