'Loophole in the benefit cap'
A cap on the total amount of benefits that people aged 16 to 64 can receive has begun rolling out across England, Scotland and Wales.
Couples and lone parents will now not receive more than £500 a week, while a £350 limit applies to single people.
The cap is part of the government's overhaul of the benefits system, the biggest since the 1940s.
Shadow Secretary of State for Work and Pensions Liam Byrne told the BBC there is a loophole in the benefit cap.