British Pound Sterling and U.S. Dollar notes are seen in this June 22, 2017 illustration photo.
Income tax cuts, a drop in property taxes, tax-free shopping for overseas visitors and the scrapping of a planned corporation tax rise are all aimed by the government at giving households and businesses a boost.
It was last down 1.36% against the dollar at 1.1106 , a new low since 1985.
The FTSE 100 (.FTSE) dropped 1.3%, hitting its weakest level since July 15, but shares in UK homebuilders jumped after Kwarteng announced changes to property stamp duty.
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