Ofgem has issued a warning to some of the country's biggest domestic energy suppliers over the gas and electricity prices they offer to online customers.
This is Money noted the practice of offering consumers cheaper energy tariffs for arranging their deal over the internet could be unlawful and harmful to competition as smaller firms are unable to match the heavy discounts on offer.
A spokesman for Ofgem said: "We are considering very carefully whether some of the energy companies are abiding by the strict rules governing the timing of short-term online deals."
Chief financial officer of First Utility Darren Braham added this form of "predatory pricing", which sees gas and electricity suppliers making a loss on these customers, could drive smaller domestic energy providers out of business.
Recently, Scottish and Southern Energy announced it will be ending discounts for online gas and electricity consumers, saying such large price differences between online and offline deals cannot be justified on cost grounds.
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