Liam Bailey, Knight Frank's global head of residential research, said: "It is too early to see the impact of the proposed wealth taxes in France in terms of actual purchases in London.



"But there is strong evidence from our web search statistics.



"This evidence from web search activity backs up a noticeable spike in anecdotal comments from our office network, where French applicants have become much more noticeable in recent months."



Prime minister David Cameron angered the French last month when he said he would "roll out the red carpet" to wealthy French citizens and firms who wanted move out and pay their taxes in Britain.