Russell Brand lost his temper after he was asked how much he pays to rent his London home - believed to be a £5000-a-month (NZ$10,000) bachelor pad.
The 39-year-old comedian joined hundreds of tenants from the New Era Estate in east London, who marched on Downing Street because they have been threatened with eviction.
But Brand, who claims "profit is a filthy word" despite being worth £9 million (NZ$18m), called a journalist "snide" because he asked the value of his home and how much he pays in rent.
The star has been calling for an anti-capitalist revolution in a series of video blogs filmed in a flat in trendy Hoxton, where he is understood to live.
Brand sold his Hampstead town house in 2010 for £2.3 million (NZ$4.6m) and then bought a £4 million (NZ$8m) mansion with then wife Katy Perry, before buying a £1.4 million (NZ$2.8m) home in the Hollywood Hills when they divorced in 2012.
He said his current London home "is down the road" from the affordable housing estate he is supporting.
Residents currently pay £650 (NZ$1300) per month but the owners reportedly want them to pay £2000 (NZ$4000) - the market rate in an area now loved by the rich and famous.
More than 90 households within The New Era Estate in Hoxton, East London, fear the plan to charge "market rents" will treble their bills and force them out of the area.
Channel 4 News reporter Paraic O'Brien asked Brand whether he was part of London's housing problem with vast swathes of homes being bought up by the super rich or rented for sky-high prices.
Brand denied this and said: "It's rented. I'm not here to talk about my rent, mate," before he dragged New Era Estate resident Lindsey Garrett onto the screen to talk about the "important campaign".
In an uncomfortable two-minute interview with Channel 4 News, O'Brien asked why the millionaire repeatedly refused to reveal how much he paid in rent.
Brand said he was "not the problem - I am part of the solution" because he was working to "amplify the voices of ordinary people".
Pointing at No. 10 Downing Street the actor said: "There is no greater and more expensive piece of real estate in London than that one."
O'Brien responded with: "I'd say your house is probably on a par" and Brand said: "Well it is rented. We don't know the value. You'd have to ask my landlord. Blessedly I can afford my rent and I'm prepared to stand up for people who can't."
Protester Garrett was then pulled into shot and said: "At least Russell Brand is standing up regardless of how big his house is. David Cameron isn't prepared to come out of his big house and help us, but Russell Brand has."
Ending the interview, Brand told the reporter: '"Snides like you undermine it. You're a snide."
This morning O'Brien admitted he had received a great deal of abuse from Brand's supporters on Twitter and said: "Holy God. Reading my timeline from overnight. Looks like come the revolution, we "snides" are totally f******."
And in a video posted on his YouTube channel today to explain his comments, Brand said: "I'm so emotional. I shouldn't be allowed on television because I'm so easily wound up."
He added that he was "a volatile person" and described parts of his exchange with the reporter outside Downing Street as being "like a quarrel at a jumble sale".
Brand said: "I do overreact, I'm a bit of a heart-on-my sleeve type of person, because for me it's an emotional thing. Like I said, on Paxman, for me it's a real thing that reminds me of my own life and my own obligations.
"I do really genuinely care about the New Era estate, I care about the broader issue, but on that I care on a personal level because that estate is down the road from where I live.
"And with that campaign we've been working on it and thinking about it and building up to Downing Street. That's a massive moment for them - 300,000 signatures. And you get there and there's a journalist there, and you think "Ah right, maybe he'll help support it ... "
"And then when he actually does go, 'How much is your rent?'. Oh mate, come on, do us a favour. It's sort of exhausting, and that's why I had the response that I had to that."
- Daily Mail