Social media sites are likely to have only one hour to remove terrorist content in rules being drafted by the European Union, according to the Financial Times.

Removal of such content in an hour is currently voluntary, but draft rules by the European Commission that would force companies to remove it within that time frame are set to be published next month, the newspaper reported.

Companies such as Facebook, YouTube and Twitter would have to remove the content within an hour of it being flagged as illegal by law enforcement bodies. The draft regulation would apply to websites of all sizes, according to the EU Commissioner for Security Julian King. He said that policies for the removal of videos and other posts were not always clear, telling the FT: "All this leads to such content continuing to proliferate across the internet, reappearing once deleted and spreading from platform to platform."