The news led to a sharp drop in the shares of the five UK regional electricity firms which remain independent. East Midlands Electricity, which has been at the centre of recent bid rumours with Houston mentioned as a possible buyer, fell 8p to 593p. Yorkshire Electricity shares dropped 12p to close the day at 727p, while London Electricity shed 8p to 640p.
It is the second time in two weeks that US utility firms have in effect ruled themselves out of bidding for British regional electricity companies.
Last week Dominion Resources, the parent company of Virginia Electric and Power, was reportedly blocked from bidding for East Midlands by US regulators.
Houston, which owns the Houston Lighting and Power Company and is the US's ninth-largest electricity company by sales, said it had signed an agreement to buy NorAm Energy, a Houston-based supplier of natural gas.
The deal, which requires approval from shareholders and regulators, would create a combined gas and electricity utility worth around pounds 9bn with almost 4 million customers. NorAm is the third-biggest natural gas supplier in the US.
Analysts suggested the Houston deal, which should be completed by next March, greatly reduced the chances of the company buying a British utility. A buyer for East Midlands, which is widely considered to be one of the most efficient regional electricity firms, would probably have to pay around pounds 1.5bn. Adam Forsyth, an electricity analyst with NatWest Markets, said: "It certainly makes it less likely that Houston will do something in the UK. There are still other US utility firms around who could launch takeover bids, but I've felt for perhaps a month that the chances are receding."
Houston last year launched a joint bid for Norweb, the regional electricity firm in the North-west of England, with Central and South West Corporation of Dallas. But the ambitions of the two firms, who made the bid as Texan Energy Partners, were thwarted when Norweb eventually succumbed to a hostile pounds 1.8bn bid from North West Water, to form United Utilities. Bid speculation later linked Houston with London Electricity, while Central and South West went on to take over Seeboard.
Apart from Seeboard, two other UK regional electricity firms have been acquired by US companies: Sweb by the Southern Company of Atlanta, and Midlands by Avon Energy Partners, a combination of General Public Utilities of New Jersey and Ohio-based Cinergy.
Houston's chairman, Don Jordan, said the takeover of NorAm would enable the combined group to offer customers bundled electricity and gas products as the two markets converged. "This acquisition will substantially strengthen Houston Industries' strategic position given these rapid changes in the industry."Reuse content