Google has accused Apple, Microsoft, Oracle and "other companies" of trying to make Android smartphones more expensive to consumers by running a "hostile, organised campaign" against it by using "bogus patents" acquired from the bankrupt Canadian company Nortel and their existing patent holdings.

Its chief legal officer, David Drummond, alleges that the companies are effectively imposing a "tax" to push up the price of Android devices. "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," Drummond wrote in a blog post.

But Microsoft has hit back, with its general counsel Brad Smith claiming on Twitter that Microsoft invited Google to bid jointly for the Nortel patents – and was turned down. Representatives from Apple and Oracle declined to comment.

Drummond alleges that the rival companies are using an "anti-competitive strategy [which] is also escalating the cost of patents way beyond what they're actually worth" and using them to stifle innovation.

Drummond writes that "in this instance 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".

He asserts: "Microsoft and Apple's winning $4.5bn (£2.7bn) for Nortel's patent portfolio was nearly five times larger than the pre-auction estimate of $1bn. Fortunately, the law frowns on the accumulation of dubious patents for anti-competitive means – which means these deals are likely to draw regulatory scrutiny, and this patent bubble will pop."

A consortium including Microsoft, Apple and RIM won the bid for the Nortel patents, which cover a number of communications technologies, against a consortium of Google and Intel. Google had made a preliminary bid of $900m before the auction, but was eventually outbid despite having large reserves of cash.

Drummond says: "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. 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."

Microsoft has sued Motorola and Barnes & Noble, claiming that their use of Android infringes patents that it holds, while Apple has filed a number of similar suits asserting patent claims against other companies.

HTC has admitted that it is paying Microsoft a set amount for each Android device it sells. The amount has not been disclosed but it is believed to be between $5 and $15.

Apple recently won a ruling in the US that HTC infringes patents covering the iPhone. And Oracle is currently suing Google in a multibillion-dollar lawsuit alleging that Android infringes copyright relating to its Java programming language, acquired through the purchase of Sun Microsystems.

Google launched its Android mobile operating system at the end of 2007, with the first phones appearing about a year later. It makes it available for free to handset makers, unlike companies like Microsoft which charges around $15 per handset using its Windows Phone software.

Android phones have exploded in popularity, making more than a third of all smartphones sold around the world. The platform has displaced the former leader Nokia, which is abandoning its Symbian operating system in favour of Windows Phone. Apple and RIM have their own mobile operating systems which they do not license.

Google has been hampered by a lack of intellectual property in wireless telephony, which has exposed it to patent-infringement lawsuits from rivals such as Oracle.

Drummond says Google is looking to strengthen its patent portfolio; it recently bought more than 1,000 patents from IBM. It is also in talks to buy InterDigital, a key holder of wireless patents valued at more than $3bn, according to the Wall Street Journal.

The most valuable patent it uses covers its "PageRank" search algorithm used for organising its search results: it has an exclusive licence on that from Stanford University, where Sergey Brin and Larry Page developed it. Though the PageRank patent is now available for licensing, Google has the rights to determine who can license it.

Patent acquisitions are expected to accelerate, with IBM and Kodak often mentioned as shopping for intellectual property on the market.