Fresh data from Halifax shows that the average house price in a UK city increased by 10.3% annually in June, to £287,440.

Across the same time frame, average earnings for city dwellers rose by 2.1%, to £35,677. This means the average city house now costs 8.1 times the average earnings of a UK adult.

The bank says that between 2011 to 2013, this price to earnings ratio (PE ratio) stayed at 5.6 times but has since risen for eight years on the trot.

Perhaps surprisingly, however, the average PE ratio for the UK across the whole is 8.5, translating to an average house price of £327,691 to a PE ratio of £38,600.

This is the widest gap recorded between cities and the country as a whole since 2014.

Halifax also scores UK cities on their affordability. A PE ratio of 4.7 means that Londonderry tops the table on this front, closely followed by Hull. The average house price in these two conurbations is £155,917 and £156,924, respectively.

And the least affordable city, shouldering a PE ratio of 14 times is Winchester, where the average house price is £630,432. Average earnings in this city are £45,059.

In London, the average house price is £564,695, giving a PE ratio of 11.

Halifax managing director Russell Galley says: “We can see from our research that affordability is significantly better in the North and there are now just two cities – Plymouth and Portsmouth – with better than average affordability in the South.

“Rising house prices have generally continued to outstrip wage growth, which reduces overall affordability, however the picture is mixed for buyers. “For city home-movers who want to stay in their area, the level of equity in their current property is likely to be an important factor in how affordable the local area is for them, whereas raising a deposit remains an issue for many first-time buyers.”

Meanwhile, Knight Frank head of UK residential research Tom Bill comments: “Demand has outstripped supply in many parts of the UK property market this year, which has put upwards pressure on prices and made some areas less affordable.

“However, as the stamp duty holiday winds down and the UK economy fully re-opens, higher supply means price growth should calm down.

“It would be wrong to expect a price crash of the sort we saw after the global financial crisis because of the checks and balances that now exist in the mortgage market, the gentle trajectory for interest rates and the rapidly-improving economic backdrop.”