The pound lost almost 1% against the US dollar, trading at $1.5743, following a stream of weak news about Britain's economy.
The RICS housing market survey found that house prices fell in July for the first time since July 2009, with a continued lack of mortgage finance also deterring first-time buyers.
Tui Travel, Europe's largest travel company, warned its profits would be hit by the uncertainty created by the austere emergency budget. Concerns about the economy made Britons delay their holiday decisions.
The shares plunged 9%, or 20.8p, to 204.8p.
