The use of electronic 'E-cigarettes' has tripled over the last two years, with over 2 million Britons now regularly smoking them.
Health charity ASH released figures showing a rise from 700,000 in 2012 to 2.1 million this year.
The group said two thirds of e-cigarette smokers still smoke normal cigarettes, while the remaining third were former smokers.
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The Chancellor will promise to fix a glitch, which means repayments continue to be taken for up to 12 months after the loan is paid off.
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