Two more companies have joined British Gas and EDF in announcing large prices rises to cover the increase in the cost of fuel.

E.On is increasing its gas prices by 26% and electricity by 16% for domestic customers, while Scottish and Southern Energy is putting gas up by 29.2% and electricity by 19.2%.

The UK is particularly vulnerable to changes in the wholesale price of fuel as it can no longer rely on its own reserves from the North Sea.

The number of households in fuel poverty - where 10% of income is spent on fuel bills - is now expected to increase to over 5m.

Scottish Power and Npower have yet to announce rises in the round of increases but are expected to do so in the coming weeks.