Mark Thompson today accused satellite broadcaster BSkyB of trying to sabotage the digital switchover process in a bid to recruit more customers.

The BBC director general said Sky was "implacably opposed" to the government's plans for switchover and against the development of digital terrestrial TV service Freeview.

And he suggested the BSkyB's chairman, Rupert Murdoch, was trying to use his influence to get the government to "put a squeeze" on the licence fee.

Defending the corporation's bid for an inflation-busting rise in the licence fee, Mr Thompson said the digital switchover process had to be properly resourced or it would fail.

"Of course, some of those who have been lobbying in private and public against our licence fee proposals do not wish the government's plans for digital switchover well," Mr Thompson said in a speech to the Smith Institute in London.

"Sky, for instance, is implacably opposed to them. They believe that the build-out of digital terrestrial is quite unnecessary and that those people who can't currently get Freeview or cable should simply be told to use Sky if they wish to convert to digital.

"The licence fee is the main funding mechanism for switchover. If you want switchover to be abandoned or fail, what better place to start than to try to use your influence - that influence which Rupert Murdoch boasts about so freely in this week's New Yorker - to put a squeeze right now on the licence fee?"

A Sky spokesman countered: "This is a predictable and transparent attempt to divert attention from the real debate about the licence fee.

"It should not be allowed to distract attention from the legitimate questions that many people are asking about value for money and the scope of the BBC's activities."

Nearly 30% of households have yet to switch to digital ahead of the switchover process scheduled to take place between 2008 and 2012.

But only around three-quarters of households are able to receive Freeview, while cable reaches only half of the country. Freeview's coverage will be extended to nearly all of the UK by the end of switchover process.

But for now satellite is the only means of getting digital for many households.

This does not necessarily mean paying a subscription, as Sky offers a Freesat service that gives access to multichannel TV for a one-off installation charge.

Plans from the BBC and ITV to launch their own Freesat service have languished, however, and many in the industry suspect they may never materialise.

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