Single workers earning an average wage would need a mortgage worth seven times their salary to buy an average Oxfordshire home.

Spiralling property costs mean that, without outside assistance, ownership is virtually impossible for single people and is a struggle for couples.

The problems are also creating a skills shortage, with young people being forced to move away from the county and would-be employees deterred by the cost of living.

Figures from HM Land Registry show that the average cost of a house in Oxfordshire is £158,865. Last year the figure was £145,718. The national average is £110,570.

The Office for National Statistics says the average salary for adults working full-time in the county is about £23,000. The national average is around £22,000.

Traditionally, banks and building societies lend around three times a person's salary for a mortgage, or two-and-a-half for a joint income.

Due to increasing competition and low interest rates, some have now increased that rate to five times a borrower's salary, but even that would not be enough for many people living in the county.

Bernard Clarke, spokesman for the Council of Mortgage Lenders, said: "It would be highly unlikely for mortgages at seven times peoples' salaries to be given.

"But many people put a large deposit down when buying to reduce the mortgage amount. That means the average loan amount is now, nationally, 2.3 times a person or couple's salary."

Mary Flavelle, spokeswoman for Oxfordshire Chamber of Commerce and Industry, said the problem was having an adverse effect to industry. She said: "The taxpayers of Oxfordshire pay for young people's education but then the skills go elsewhere when they are forced to leave because of house prices.

"The only option seems to be creating more affordable housing but in the past these homes have been bought up by landlords who then lease them to students."

Tanya Hall, head of Oxford lettings for estate agents Knight Frank, said: "I can see why it would be practically impossible for most people to buy. We have clients who plan to rent for a short period until a house appears at the right price but they end up staying with us for years."

The Financial Services Authority has warned first-time buyers not to overstretch themselves financially to buy a home. It says house prices will eventually fall, leaving people who paid high prices with negative equity.

Economic changes that mean less cash in peoples' pocket would also make repayments hard.