Two more energy suppliers have announced they are to hit customers with steep price hikes.

Scottish & Southern Energy, which has 8.8 million UK customers, is raising gas prices by 29.2 per cent and average electricity costs by 19.2 per cent from Monday.

Fellow 'big six' supplier E.ON, which has 5.5 million UK customers, unveiled rises of 26 per cent and 16 per cent in gas and electricity prices respectively.

Both firms blamed soaring wholesale energy prices.

The price rises follow similar moves from rivals British Gas and EDF.

Customers who take both gas and electricity from E.ON will see annual bills rise by 22 per cent, or £227, to an average of £1,226.

Graham Bartlett, the managing director of E.ON's retail business, said: "I'm very aware of the effect that today's announcement will have on our customers and I recognise that this is a very tough time for everyone."

He added: "This was not an easy decision to make and we've tried to keep these increases as low as possible while protecting as many of our customers as we can."

The move comes a day after wholesale gas prices jumped more than 14 per cent when a leaking North Sea pipeline prompted fears about supplies this winter.

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