Britain six biggest gas and electricity suppliers are under pressure from consumer groups to cut their tariffs after E.ON trimmed its standard gas prices by 5.1%.

Gillian Guy, Chief Executive of Citizens Advice, said: “It is encouraging that E.ON is to cut its gas bills but the reduction in savings for people will be modest. The company should also help customers by cutting electricity bills.

“The industry as a whole urgently needs to step up to the plate - suppliers need to play fair with customers and start passing on the major savings they have been making from cheap wholesale costs.”

Richard Lloyds, Executive Director at consumer body Which?, said: “E.ON has taken the first step by cutting its prices for gas deals but given plummeting wholesale costs, consumers are bound to question if it’s enough.”

‘Other risks’

Ann Robinson, Director of Consumer Policy at price comparison website Uswitch, added: “Now is the time for the other major suppliers to step up to the plate and offer decent, double-digit reductions to help hard-pressed consumers – many of whom are rationing their heating this winter just to make ends meet.

“Wholesale electricity costs fell 23% last year, so why have we not seen a single reduction to big six standard electricity tariffs?”

Tony Cocker, Chief Executive of E.ON UK, defended the level of the cut, saying: “The underlying position is that whilst the price we pay for our customers’ energy has fallen, we also have to take account of managing the various other risks in the market that can change, and the fact that many of the other costs that we don’t control but do have to bear have increased or may increase.

“Once you’ve built in various uncertainties and other factors, whilst the wholesale market movements may translate across to a dual fuel domestic bill for a drop in prices of under 10%, the inclusion of those other factors translates the percentage to the standard gas cut announced today.”

Meanwhile consumer group Which? has said that Britain’s “big sixg” energy suppliers are still failing customers.

Richard Lloyd, Executive Director at Which?, said: “With energy customers facing big bills this winter, energy companies need to up their game and provide the service their customers deserve.

“We hope the competition inquiry into the energy market proposes radical ways to shake up the energy market and find ways to ensure millions of people can switch to better deals while also protecting vulnerable customers from paying over the odds

> See E.ON's statement