Homebuyers have been at the epicentre of the credit crunch since it hit last autumn. Mortgage approvals for new homes have slumped as lenders rushed to withdraw products, tighten terms and raise interest rates in silent recognition that cut-throat competition had previously prompted at least some banks and building societies to suspend their more sober risk assessment.

But although the market for mortgage-backed securities has nearly come to a standstill, there has been little evidence to justify a market panic.