Conservative leader David Cameron has demanded urgent action to tackle what he calls the growing gap between rich and poor due to high property prices.
Soaring house prices have made it hard for first-time buyers
He warned of "a growing inequality at the heart of British life" because the property ladder was beyond young people from less well-off families.
He called for more housebuilding to provide an adequate provision.
Mr Cameron's comments in a Sunday newspaper come ahead of a major speech he is to make on housing on Monday.
In an article in the Independent on Sunday, the Tory leader said: "There is a growing inequality at the heart of British life which politicians desperately need to address.
"How can we bridge the widening gulf in our society between those who benefit from being on the property ladder and those who are kept off?
"This is a challenge that goes to the heart of the sort of society we want to build.
"For pressing reasons of social justice, and economic efficiency Britain needs to spread the benefits of ownership more widely."
He said millions of new houses would be needed over the coming decades because a shortage of new homes had contributed to an "affordability problem" for first-time buyers.
But the ones from wealthy families could rely on loans or gifts from their parents, a state of affairs which "only entrenches unfairness".
Mr Cameron mocked opponents of new developments as people who want to Build Absolutely Nothing Anywhere Near Anyone or "Bananas".
Housing minister Yvette Cooper said his claims had no credibility because his party had opposed the government's plans for more house-building nationally.
"His party remains committed to cuts in the housing budget and his frontbench spokesmen are continuing to oppose new homes in their own constituencies," she said.