Energy supplier EDF has raised electricity prices by 17 per cent and gas prices by 22 per cent.

The company blamed record wholesale energy costs for the increases, which come into effect immediately.

The French firm is one of Britain's biggest energy suppliers, with 5.1 million customers.

The hikes will mean a typical customer using gas and electricity will pay £3.97 a week more for their energy, it said.

EDF spokesman Eva Eisenschimmel said: "Record world oil prices have continued to drive up wholesale gas prices.

"Alongside unprecedented rises in wholesale coal and electricity costs, this has impacted hugely on the cost of supplying energy to our customers."

The company said wholesale energy prices had increased by 70 per cent for coal, 63 per cent for gas and 47 per cent for electricity since it last increased prices in January.

British Gas said its prices have not changed, but an independent report commissioned by owner Centrica last week warned prices could increase by 70 per cent.

Tim Wolfenden from price comparison website uSwitch.com said: "Although EDF Energy is the first supplier to succumb to the inevitable, this is not going to be a unilateral move.

"Other suppliers are suffering too and are sure to follow suit over the next weeks or months."

EDF and Centrica are set to announce that they have bought UK nuclear firm British Energy for £12 billion, according to reports.

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