Rupert Murdoch's News Corp has confirmed that it plans to strengthen ties with John Malone's Liberty Media by acquiring its 21% stake in Gemstar-TV Guide.

Liberty Media is transferring its Gemstar stake to News Corp in return for 121.5 million News Corp American Depositary Receipts (ADRs), making it the company's top non-voting shareholder, after Murdoch and his family, with an 18% stake.

The deal also makes News Corp, which already owns a 21% stake in Gemstar-TV Guide, the leading shareholder in the electronic programme guide specialist.

The complex deal, announced today (September 27), also gives Liberty Media shares in Murdoch's proposed global satellite platform Sky Global Networks. In addition, Liberty will buy an additional $500m of Sky Global shares when it floats later this year.

The tie-up between two of the world's leading media titans is expected to put Murdoch in a stronger position to bid for US satellite operator DirecTV, owned by General Motors' broadcasting division Hughes Electronics. However several other players, including DirecTV rival EchoStar, are expected to bid for either the DirecTV operation or Hughes as a whole. General Motors is expected to put Hughes on the block within months.