House prices are set to fall hard in London, Savills has predicted, with Stamp Duty rather than Brexit to blame.

The firm says that in prime central London, house prices will tumble 9% this year, after falling since 2014 (down 0.4% in 2014 and down 3.3% last year).

House prices in other prime London areas did not fall in the last two years but will dip 5% this year and 1% next, says Savills.

The firm is predicting flat house prices in prime central London next year and the year after, before 8% growth in 2019.

In other prime London markets, Savills sees flat growth in 2018, followed by 4% growth in 2019.

Savills has revised its five-year forecasts for London, saying that its researchers do not believe the current situation will mirror the crash of 2008, but could be reminiscent of 2002 when the market was hit by a stock market downturn.

The firm says: “The prime central London markets, where values average around £4m, have been most impacted by changes to Stamp Duty since December 2014. Prices were 8.1% below their 2014 peak by the time of the referendum, including falls of 2.2% in the first six months of this year.

“As a result, Savills believes that further price adjustments in the order of 6% or 7% will be required to secure sales as buyers wait to see how Brexit negotiations proceed, and the impact on the UK and London economy becomes clearer, although the currency play is a clear boost to international buyer interest.

“Prime central London values are therefore now expected to close 2016 down 9% and stabilise for the next two years.

“The lower value, more domestic outer prime London markets, where the average house price is £2m, were less impacted by the December 2014 Stamp Duty increases and values rose 2.3% in 2015.

“However, a further 3% surcharge on additional homes combined with pre-referendum uncertainty to suppress growth in the first six months of this year and contributed to reduced fluidity in the market.”

Lucian Cook, Savills head of research, said: “The summer market was slow but certainly not moribund, and the currency advantage brought international buyers back into the market.

“We now need further small adjustments to bring buyers back to the table in greater numbers and early signs from the autumn market are that committed sellers have adjusted their prices by between 5-10%.

“The current situation is reminiscent of the 2002 to 2004 post-bull run period when a less significant financial shock combined with an uncertain geo-political backdrop. Prices then fell a total of 10%.”

Another London agent, Richard Barber of WA Ellis, part of the JLL Group, was more upbeat, saying that last week his firm received over £35m of offers for properties in Knightsbridge, all within 5% of asking price.

However, he said that vendors had to be “prepared to sell in line with the current market”.

Knight Frank, in a new residential review of the London market, said that Stamp Duty increases have had a “sizeable” impact on demand and transactions, with “few signs” of transactions increasing in central London.