Regulator Ofgem is set to launch an investigation into four of Britain's energy suppliers, it has emerged.
According to the Financial Times, the watchdog will probe EDF Energy, Scottish Power, npower and Scottish and Southern Energy over concerns about mis-selling to customers.
Ofgem is expected to announce the investigation today and said that it plans to take strong action if the energy suppliers in question are found guilty of not adhering to industry regulations.
New rules introduced last year stipulate that all customers must be supplied with estimates before face-to-face sales are concluded and consumers must be given comparisons between their current deals and new offers before they switch energy providers.
Ofgem has the power to fine energy suppliers up to ten per cent of their turnover if they breach these regulations.
David Mannering, corporate economic regulation director at npower, told the BBC: "We fully support Ofgem in making sure that customers clearly understand the products on offer to them and we are confident that the processes we have in place mean that we comply with our regulatory obligations."
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