Rupert Murdoch's bid to take full ownership of BSkyB (he owns a 39 per cent stake) provides the coalition with its first big test on media ownership. David Cameron will want to avoid any suggestion that he pre-approved this deal in return for the support of Murdoch's newspapers, but he may struggle to do so.
We know that Murdoch visited Downing Street just a week after Cameron was appointed Prime Minister. Was News Corp's plan to take full control of Sky discussed? It would be surprising if it wasn't.
There is also no doubt that Murdoch timed his bid to coincide with the election of a government more sympathetic to calls for media deregulation. As I've previously noted, Cameron has already appeased Murdoch by agreeing to abolish Ofcom and potentially freeze or cut BBC funding.
The Lib Dems, however, may not see things the same way. It was the Murdoch-owned Sun, after all, that launched a series of crude, demagogic attacks on Nick Clegg after his success in the first leaders' televised debate. And, as David Prosser notes in today's Independent, it is Vince Cable, as Business Secretary, who will have to provide regulatory approval for any deal.
From one perspective, there is no decent objection to Murdoch acquiring full control of Sky. It was Murdoch who invested millions in the company, almost bankrupting News Corp in the process, and who had the foresight to recognise the immense potential of satellite television.
But the extent to which Sky will interact with the other divisions of Murdoch's media empire raises obvious public-interest concerns. As Prosser writes:
You won't see print journalists from beyond the News International stable being used as pundits on Sky News, for example, and it can't be long before Sky subscribers are offered special deals on the newspapers' internet operations, now they are being moved behind the paywall.
In a digital age, in which Sky produces huge amounts of text-based content and the Times produces ever more visual content, the boundaries are increasingly blurred.
It is for this reason that Cable must order Ofcom to review the takeover and its implications for British media. Cameron must not be allowed to cave in to Murdoch again.