Downing Street is the third biggest Twit in the world -

Downing St has fallen foul of a Twitter regulation designed to stop malicious organisations sending spam.

Twitter has banned the Prime Minister's office from 'following' any more individuals and organisations, after it gained the dubious honour of following the third highest number of people of any Twitter user in the world.

But Twitter has rules about this sort of thing - it calls it 'aggressive following' - as it's a tactic often used by attention-seekers and Viagra salesmen to increase their presence on the network.

A spokesman for Number 10 promised TechEye there was nothing sinister behind following so many people. He said the account had inadvertently been set up in such a way that anyone who elected to receive its messages was automatically followed in return.

By now, though, Number 10 is following half a million other Twitter users. This means that Cameron's office is getting constant status updates from each and every one, on topics from Mabel's pet cat to who snogged whom at the Young Conservatives summer party.

To make matters worse, the site was initially set up under Labour, so a lot of these posts might not be exactly what the Tories want to hear.

Apparently the average Twitter user posts four and a half tweets a day, so we're talking two and a quarter million messages for poor beleaguered Dave, every single day. The spokesman said he didn't think anyone was reading them.

This time last year, David Cameron remarked that the reason he was not then using Twitter was that "too many twits might make a twat".