A property specialist says the higher end of the London property market could face "complete and utter collapse" as a result of the changes to stamp duty announced yesterday.

George Osborne on Wednesday overhauled the stamp duty system, cutting stamp duty for 98pc of buyers but increasing the levy for homes worth more than £1.5m.

Naomi Heaton, chief executive of London Central Portfolio - a firm which buys and manages high-end London property on behalf of investors - says people "who work really hard and are successful people" could end up paying 50pc more tax.

As a result of 20pc price hikes in London over the last year there are more families than ever before living in million pound plus homes, who will also be affected, she said.