“In one of his central policies due to be unveiled in his closing speech, Cameron will say: “For years politicians have been talking about building what they call affordable homes but the phrase was deceptive. It basically means ones that were only available for rent. What people want are homes they can actually own.

“When a generation of hardworking men and women in their 20s and 30s are waking up each morning in their childhood bedrooms, that should be a wake-up call for all of us. We need a national crusade to get houses built. That means banks lending, government releasing land and, yes, planning being reformed.”

In the key reform, ministers will change the definition of affordable housing to include not just properties for rent, but starter homes, as part of the government’s programme to build low-cost homes for first-time buyers so long as they are under 40 years old. It will mean developers will have fulfilled their obligations to a council if they build homes for purchase.

Under the scheme, houses must must be 20% below the market rent and capped at £450,000 inside London and £250,000 outside. …