Recently unemployed adults may have to wait five weeks before they get any benefit payments, according to a new report.
The report, published ahead of the latest unemployment figures, said the new five-week wait will apply to anyone making a fresh claim for social security benefits.
The union organisation said it was a "new and deliberate delay" which could distract new claimants from looking for work and drive them into the hands of payday loan firms.
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Unpaid internships should be banned to prevent young people missing out on jobs in top professions, a new report has said.
The study by the National Childbirth Trust and National Federation of Women's Institutes found a lack of staff left some women frightened.
Extracts released by 10 Downing Street suggest Mrs May will say the UK will not settle for a "half-in, half-out" policy.