The government is discovering that wishing for housing to be more affordable, as they did for several years, creates an uncomfortable world of negative equity, weak banks and mortgage famine. They by now should have worked out that their theory that you needed to build more houses to bring house prices down was completely wrong. We today have plunging prices at the same time as large cuts in new building.

So when will housing be affordable? There is no single good price level, as it all depends on what price level the mortgage banks will support. They, under strong regulatory influence both ways, have lurched from believing very high prices are affordable, to working with much lower prices. What is affordable when banks will lend 5 times salary is not affordable when they will only lend 3 times salary. What was affordable with a 100% mortgage may not be affordable with an 80% mortgage.

The boom was so overdone in London that even people on good incomes were priced out of the London housing market unless they already owned a property or had some other windfall to help them. Still today, after considerable falls in the market, a new MP on £63,000 a year would be hard pressed to find anything more than a studio flat he or she could afford north of the river near the office. A professional, middle manager or Doctor on around £100,000 would have little choice of anything other than a one bedroom flat in the central districts if they were starting out with a mortgage and not much else. Pity anyone on average wages, they do not have a chance in inner London.

I fear this all means the fall has further to go. The government has not yet found a way to help mend the banks. The mortgage market is still far from happy. Northern Rock is in effective run off, so Northern’s mortgages need refinancing elsewhere as they fall due. On current policies we have not found a base for the property market. That means more losses at the taxpayer financed banks, in line with the deteriorating loan experience revealed by HBOS in their figures yesterday. Taxpayers are currently losing more than £7 billion on the bank shares the government has bought for £37 billion at current prices.

This week I asked the Foreign Secretary why it appears that Northern Rock cannot offer competitive busniess rates in the market owing to EU competition rules, but this constraint does not seem to apply to RBS. He said he would write to me with an answer. I think we need to know, as it seems odd that the smaller bank is prevented from writing much new business, whilst the bigger bank is unaffected.