Ofgem is probing the energy giant to see whether it breached licence conditions by failing to waive termination fees when customers switched to another provider

Under current regulations, fixed tariff customers looking to switch to another provider can do so for free up to 49 days before the contract is up.

The investigation comes following concerns raised by consumer affairs site MoneySavingExpert.com which claimed customers were wrongly being told to pay £60 to exit the deals early.

Alex Neill, Which? managing director of home products and services, said: “Suppliers should be making it as easy as possible for customers to switch. If British Gas is found to have put off customers who wanted to switch, then the regulator must swiftly hold them to account.”

A British Gas spokesperson, said: “British Gas will co-operate fully with Ofgem to address the issues raised in today’s announcement.”