By Daniel Hunter
Houses prices in some of London's most expensive areas have fallen by as much as 22% since autumn 2014, according to property services group LSL.
Westminster saw the full 22% fall since September, while prices in Kensington and Chelsea fell 16% since November.
LSL said the changes to stamp duty rules had an impact on prices. Based on the average prices in Kensington and Chelsea, anyone buying a house in the area would have to pay £118,000 in stamp duty alone.
"This fall-off in the top tiers of the market has cooled activity levels too," said Adrian Gill, director of Reed Rains and Your Move estate agents, part of the LSL group.
Mr Gill also said that the number of homes being sold in London fell 16% in the year to April, adding to concerns over a lack of available homes.