According to a regular snapshot of values by Knight Frank, the international estate agency, land values in prime central London have now risen by 48 per cent since September 2011. The average price for greenfield residential development, meanwhile, rose by a far more modest 2.3 per cent last year, decelerating from a 5.3 per cent increase in 2013.

The figures show a marked contrast between London on the one hand, and other parts of the UK, Knight Frank said.

In recent years, London’s residential property market has seen prices soar on the back of ultra-low interest rates and associated investment buying, such as from wealthy overseas buyers. The surge in prices has prompted some political pushback: last year, the UK finance minister, George Osborne, removed some of the tax reliefs that overseas investors can enjoy in property. The issue of a possible “mansion tax” on high-value property remains controversial ahead of this year’s annual general election in May.