Broadcaster and writer Victoria Coren Mitchell put forward a radical answer to London's housing crisis, arguing rich people in "iceberg houses" would be left helpless if nurses, firefighters and young people fled the capital.
Her suggestion on BBC One's Question Time followed a young woman telling the audience she was leaving London because housing is unaffordable.
"There's plenty of room to build luxury houses, luxury apartments," the woman said. "I can't afford them."
After Tory Cabinet Minister Justine Greening and Labour's Chuka Ummuna argued over which party had failed to build enough homes, Ms Coren Mitchell offered an alternative.
Ms Coren Mitchell, who presents Only Connect, said: "The idea that any young person, unless they are the child of a Russian oligarch, can live in London any more is preposterous.
"In Tottenham, one of the poorest places in central Europe, a one-bedroom flat can cost you £400,000. It's a stupid amount of money.
"Of course they could build more houses. How many council houses were built in London in the last year? Probably about 40."
She went on to call for a "proper revolution".
"You will see it's easy for me to say because I'm not a politician. But I'm not, and it is, so I will," she continued.
"I think what has to happen is all of the young people, all of the workforce, just have to leave London. Work somewhere else.
"The Government has to find something to offer people outside of London, to regenerate other parts of the country, and they'll leave.
"All of these super-wealthy people with their iceberg houses with no nurses, no policemen, no firemen and no-one to clean the house, no-one to deliver the mail to houses."
House prices have rocketed in the last 20 years.
A Guardian newspaper investigation found in 1995, the median income in London was £19,000 and the median house price was £83,000, meaning that people were spending 4.4 times their income on buying a property.
But by 2012-13, the median income in London had increased to £24,600 and the median house price in the capital had increased to £300,000, meaning people were forced to spend 12.2 times their income on a house.Suggest a correction