Chuka Umunna revealed that he had been passed evidence that suggests Blue Arrow, Staffline, Acorn, Taskmaster, Randstad and Meridian - agencies employing over 100,000 people in the UK - have been involved in selling personal accident insurance to employees despite the fact that workers are normally covered by their employer’s insurance.

Umunna accused the agencies of “profiteering” from some of Britain’s lowest earners and even claimed that one company, Gee 7 Group, specialised in putting together the “dubious” arrangements for the agencies.

The government has responded to the claims by announcing an investigation into the six companies involved, and has not ruled out the possibility of a broad inquiry into the practice.

Tom Jones, head of policy at Thompsons Solicitors, said “Agencies profiteering from low-paid workers is, sadly, nothing new and I wouldn’t be at all surprised if these very serious claims are only the tip of the iceberg. People desperate for work will take it on whatever terms they are offered, they don’t have options. If these companies are taking advantage of people’s desperation it’s despicable and must be tackled head on.”