Brilliant Energy Supply Limited, an energy supplier with about 17,000 domestic customers, has ceased to trade.

The company’s customers, which include some supplied under a ‘white label’ arrangement with Northumbria Energy, will now enter Ofgem’s ‘supplier of last resort’ process and be allocated to another company.

Gillian Guy, chief executive of Citizens Advice, said, “The failure of another supplier is a clear sign Ofgem needs to urgently move forward with its reforms to better monitor existing companies and take action earlier when problems arise.”