Google has come out all guns blazing in defence of its mobile OS Android - accusing arch-rivals Microsoft and Apple of teaming up in "a hostile, organised campaign" against the platform.

Speaking via the Google blog David Drummond, SVP and chief legal officer at the search giant said:

"I have worked in the tech sector for over two decades. Microsoft and Apple have always been at each other’s throats, so when they get into bed together you have to start wondering what's going on. Here is what’s happening:

"Android is on fire. More than 550,000 Android devices are activated every day, through a network of 39 manufacturers and 231 carriers. Android and other platforms are competing hard against each other, and that’s yielding cool new devices and amazing mobile apps for consumers."

He then goes on to state that this success has led to a backlash in the tech industry and accuses Apple and Microsoft, huge competitors themselves of course, of getting "in to bed together" to acquire Nortel and  Novell’s old patents, and trying to make Google pay for the privilege of having certain licenses on Android devices.

"A smartphone might involve as many as 250,000 (largely questionable) patent claims, and our competitors want to impose a 'tax' for these dubious patents that makes Android devices more expensive for consumers," said Drummond.

"They want to make it harder for manufacturers to sell Android devices. Instead of competing by building new features or devices, they are fighting through litigation.

"We thought it was important to speak out and make it clear that we’re determined to preserve Android as a competitive choice for consumers, by stopping those who are trying to strangle it."

Microsoft has hit back, tweeting a copy of an email that seems to indicate that the Redmond company offered to work with Google. 

Microsoft's general counsel Brad Smith also tweeted: "Google says we bought Novell patents to keep them from Google. Really? We asked them to bid jointly with us. They said no."

Patent wars in the tech world are not a new thing, hardly a day goes by without yet another legal story breaking where one company is suing another. But an accusation of bed jumping? Things just got juicy...