Economists in London say the capital’s average house price will pass £700,000 by 2020 if current trends are left unchecked.

The Centre for Economics and Business Research (CEBR) says house prices will grow 54 per cent during the next six years, stretching the cost of London property way beyond the rest of the country.

The increase is almost twice that of the rest of the UK, which will inflate by 28 per cent to £307,000 in the same frame, according to the estimates.

Separately, property website Rightmove said asking prices are rising more than seven per cent a month in some London boroughs.

Brent, Camden and Haringey all saw increases of more than seven per cent last month.

CEBR said the boom was based on London’s “chronic shortage of housing, international investor appetite and an economy that is significantly more insulated from potential public spending cuts than most other regions”.