The current legal status of ISP web blocking is voluntary, but there have been a number of attempts to introduce legislation to move it onto a mandatory footing.
David Cameron first announced such legislation in July 2013 and no Government legislation to this effect occurred during the 2010-15 Parliament.
In May 2015, a leaked Council of the European Union document on the topic of net neutrality suggested users would have to opt into blocks, rather than opt out as per the current UK government's plans.
John Carr of the UK Council for Child Internet Safety said of the proposals: 'a major plank of the UK’s approach to online child protection will be destroyed at a stroke'.
The Conservatives said that they would give an independent regulator such as ATVOD the legal power to compel internet service providers to block sites which failed to include effective age verification.