Up until two years ago, emailing and tweeting was not allowed during Prime Minister's Questions, the televised, agenda-setting Wednesday morning ritual. Yesterday for the first time Prime Minister David Cameron used tweets coming in from people not in the House of Commons as ammunition to fuel the debate.

Sky News has a great report on what happened and how it developed. The PM taking on board tweets and addressing them live is a watershed moment, as now a precedent has been set, and we will see this happen more and more. More engagement is a good thing, but the deluge will need managing too...

Here's Sky News' report by political correspondent Sophy Ridge:

A little bit of history was made at PMQs today.

 

For the first time, the Prime Minister used a tweet sent from someone watching the session from outside the Chamber as ammunition at the dispatch box, almost in real time.

 

The former Labour MP, Tony McNulty, is known for off-message tweets.

While watching PMQs, he used the social networking site to say of Ed Miliband: "Public desperate for PM in waiting who speaks for them - not Leader of Opposition indulging in partisan Westminster Village knockabout."

 

Quick as a flash [...] Education Secretary Michael Gove spotted the tweet and flagged it up to David Cameron, who read it [...] less than six minutes after it was sent.

 

The incident demonstrates Mr Gove's sharp political eye (and will no doubt open up a debate about which username the Education Secretary is watching Twitter from, as he has no official account).