LONDON  - Rupert Murdoch's BSkyB wants to add an extra dimension to the April 29 wedding of Prince William and Kate Middleton.

The satcaster is considering broadcasting the signal to British cinemas and 3D TV-enabled homes as a way of generating standout coverage of an event that could have the biggest global audience in TV history.

Discussions with Clarence House and Buckingham Palace have not begun, "but if the planets align, then this is the kind of big-event TV that would definitely be a contender for our strategy of offering 3D coverage," says a Sky insider.

Sky has shown Premier League football in 3D for more than a year, and it aired the election leaders' debate, operas, concerts, ballet and the ATP tennis finals on its own 3D channel.

The 3D service can only be accessed by the 3 million-plus homes with Sky's high definition set-top box (and 3D glasses).

The strategy is indicative of the worldwide scramble as broadcasters plan coverage of the first royal wedding of the multimedia age.

"I think it is going to be a major event for many, many people in this country and around the world," says BBC director of vision Jana Bennett, who oversees the pubcaster's television, radio and online content.

Video of the Westminster Abbey ceremony will likely be made available free to accredited broadcasters around the world. BBC is looking at filming and broadcasting the event in HD and Bennett thinks it might be a driver for HD services.

"It could be a bit like the Coronation when TV sets were turned on for the first time in so many millions of households," she says.

Nearly 1 billion viewers worldwide tuned into the 1981 state wedding of Prince Charles and Lady Diana Spencer -- then broadcast by the BBC in an era when both the U.K. and the U.S. had just three national TV channels.

The 1997 funeral of Princess Diana was watched by an estimated 2.5 billion people worldwide, making it the most-viewed TV event ever.

Given the number of TV channels, online video outlets and social networking sites, viewership totals for the Prince William wedding will likely eviscerate previous records.

"We haven't gotten into the logistics of how all the media feeds will work," a Buckingham Palace spokeswoman tells THR.

BBC, ITV and Sky News are all planning live coverage, as are a host of broadcasters in the U.S. and around the world.

But despite the high tune-in, the Royal Wedding -- in 3D or not -- likely won't generate a huge payday for broadcasters because the event will air live.