Network O2 has decided it's time to start whacking up its monthly contract costs, with the UK mobile provider adding 3.2 per cent to all monthly tariffs from next February. Regardless of what you signed up for.

The changes only affect those paying monthly line rental fees, so those on PAYG deals who pay by the minute, message or megabyte won't see any changes.

To be fair to poor old O2, it sounds devastated about having -- HAVING -- to do this. On its price change page the network says: "To date, we've held off putting our tariff prices up for as long as possible. Even when our competitors raised theirs. But now, because of inflation, we need to change the price of your tariff. From 28 February 2013, your line rental will go up by 3.2%. That's in line with the current rate of inflation as at December 2012 when we made the announcement."

So if you're on a £26 a month tariff, that'll increase to £26.83 from next February, while those paying £36 at the moment will see their bills rise to £37.15. There's a checker tool on O2's site that does the maths for you, and it doesn't even have the common courtesy to display a sad-face emoticon when it breaks the news.

And, as you can see from the image above, O2 is heading off any potential complaints by pointing out the small print in the agreement you didn't bother reading that said it's allowed to raise prices whenever it wants. [O2 via Cnet]