BSkyB is to take its battle to hold on to a controversial 17.9% stake in ITV to the court of appeal.

The pay-TV satellite broadcaster, which acquired the ITV stake for £940m in November 2006, has today lodged an application with the Competition Appeal Tribunal for leave to appeal an order to sell down the stake to less than 7.5%.

If the CAT does not grant permission, BSkyB will have 14 days to lodge an application directly with the court of appeal asking for the right to appeal the CAT's judgment.

BSkyB's bid to take the legal battle to the court of appeal is a delaying the process that could help save it hundreds of millions of pounds.

Since the BSkyB chief executive, James Murdoch, snapped up the ITV stake - blocking a potential takeover by rival pay-TV operator NTL, now Virgin Media - the advertiser-funded broadcaster's share price has fallen from 135p to 35p.

In July, BSkyB made a £616m non-cash accounting impairment charge on its 17.9% stake in ITV, marking the stake at the closing share price on June 27.

ITV's share price was down 2.25p, or 5.96%, to 35.5p at 11.43pm today. BSkyB's share price was up 17p, or 4.1%, to 431.25p at 12pm.

In September, the CAT rejected an appeal by Sky over a ruling by the Competition Commission and then secretary of state John Hutton that it must reduce its holding to less than 7.5%.

Last month, it turned down an appeal lodged by Virgin Media that could have resulted in BSkyB being forced to sell the whole stake.

A Virgin Media spokesman said: "We urge the Competition Appeal Tribunal and the court of appeal to recognise Sky's application for what it is: a blatant attempt to delay an already drawn-out process still further and refuse Sky permission to appeal."

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