Some 4.82 million UK workers receive less than the living wage - the rate of pay designed to help workers to afford a basic standard of living.
The rate is currently £8.30 an hour in London and £7.20 in the rest of the country, compared with the national minimum wage rate of £6.19 an hour
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A Hamsptead mum who is in jail in Iran has ended a hunger strike after three days.
Their pleas came as charity worker Nazanin Zaghari-Ratcliffe was expected on Wednesday to be in her third day of a hunger strike.