EDF Energy on Friday increased household power and gas prices for the second time this year, while its competitors said they had no immediate plans to hike rates in response to soaring wholesale costs.

The French-owned company increased its power prices by 17 percent and gas prices for retail customers by 22 percent with immediate effect, meaning a typical customer on a dual fuel tariff will pay 3.97 pounds more a week.

The latest price hikes are about double those EDF brought in January to reflect soaring wholesale costs in late 2007.

"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," Eva Eisenschimmel, Chief Operating Officer of EDF Energy Customers Branch, said.

"We now have to pass on some of the resulting rise in wholesale costs to our customers."

The UK arm of state-run French power giant EDF pointed to a 70 percent increase in coal costs, a 63 percent rise in gas and 47 percent higher wholesale power prices since it last increased its retail prices.

MORE TO COME

Analysts and industry sources say a second round of big increases in household energy bills from all suppliers is likely over the next few months because the big utilities can only absorb the impact of soaring wholesale costs for so long.

EDF has surprised many in the sector who had expected the country's biggest utility British Gas to be the first with a new price rise. Its rivals are trying to hold off.

"There are absolutely no immediate plans to increase our prices and we will continue protecting our customers for as long as possible. That said, we are all under the same pressure," said a spokesman for RWE npower, which was the first to move in the sector-wide price hikes early this year.

A spokeswoman for E.ON UK, part of German utility E.ON, said the company had "no current plans to change our prices" but would continuing to monitor the market.

Wholesale power and gas prices have fallen over the last week, led by a sharp drop in the price of oil which has been the main factor driving up energy costs globally over the last year.

Despite the recent, and many believe short-lived, decline in oil, wholesale gas contracts for next winter are still more than 50 percent higher than they were in late January-early February.

"Costs remain high, including coal and gas, and we continue to monitor our pricing structure against these factors and also against the market," a spokesman for Scottish Power, the UK subsidiary of Spain's Iberdrola said on Friday.

Industry sources say it can take several weeks to prepare for changes to utilities retail pricing but say EDF's competitors will likely hike prices before the winter sets in, driving up demand for gas and power.

Because household demand for gas in particular is low during the summer, as it is mainly used for heating, the losses for suppliers more easily absorbed.

But industry sources say suppliers will want to raise their prices before winter arrives to avoid much bigger hits on their balance sheets.

The chief executive of Scottish and Southern Energy, Ian Marchant, said on Thursday said his company was holding back from passing on rising prices, but joined rival British Gas-owner Centrica in warning that big hikes were likely on the way soon.

"I can't see it won't happen before winter," he said..