Facebook and Twitter are preparing to stand firm against government ministers' calls to ban people from social networks or shut their websites down in times of civil unrest.

The major social networks are expected to offer no concessions when they meet the home secretary, Theresa May, at a Home Office summit on Thursday lunchtime.

Ministers are expected to row back on David Cameron's call for suspected rioters to be banned from social networks, such as Twitter and Facebook, following the riots and looting across England a fortnight ago.

The home secretary will explore what measures the major social networks could take to help contain disorder – including how law enforcement can more effectively use the sites – rather than discuss powers to shut them down. The acting Metropolitan police commissioner, Tim Godwin, and the Tory MP Louise Mensch have separately explored the idea of shutting down websites during emergencies.

Surely it makes sense to keep them up, if not simply for evidence collection later?

British governments have commented several times on the control of information in China.