Londoner Leo Alexander insisted that for some under-25s, housing benefit is "a necessity".
He left home at 18 due to family breakdown and said the money he receives goes straight towards subsidising the cost of the hostel he lives in.
"It's kind of like a lifeline for a young person who leaves home with things like family breakdown or suffering domestic abuse," he said.
George Osborne today said that he would "look at housing benefits for the under-25s."
"There are plenty of people listening to this programme who can’t afford to move out of their home, but there are people on benefits who can get housing benefit under the age of 25," he told BBC Radio 4.
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