Scottish Power is planning to float between a quarter and a half of its telecoms and Internet business by the end of the year in what will be Scotland's biggest new listing.

The power company said it would retain a majority stake in fast-growing Scottish Telecom, which analysts expect to be valued at around £1.5 billion sterling. "The board of Scottish Power believes it is now timely to realise value for Scottish Power shareholders through an initial public offering," said the chief executive, Mr Ian Robinson.

The telecoms business poised to be listed - which does not include Scottish Power's mobile phone operations - saw annual revenues rise by 100 per cent to £166 million last year.

"Hopefully, the flotation of this vehicle will have a similar effect on the Scottish Power share price to the effect that Energis had on the National Grid when that was partially floated," said Philip Hollobone of WestLB Panmure.