According to a leaked white paper, the plan seems similar to Australian legislation that threatens huge fines for social media companies and jail for their executives if they fail to remove "abhorrent violent material" from their platforms rapidly.

The UK plan creates a new statutory duty of care, to be policed by an independent regulator and likely to be funded through a levy on media companies. The regulator -- likely initially to be Ofcom, but in the longer term a new body -- will have the power to impose substantial fines against companies that breach their duty of care and to hold individual executives personally liable.

The law will apply to social media platforms such as Facebook, search engines, online messaging services and file hosting sites. Other proposals in the online harm white paper include:

• Government powers to direct the regulator on specific issues such as terrorist activity or child sexual exploitation.
• Annual "transparency reports" from social media companies, disclosing the prevalence of harmful content on their platforms and what they are doing to combat it.
• Co-operation with police and other enforcement agencies on illegal harms, such as incitement of violence and the sale of illegal weapons.

"Companies will be asked to comply with a code of practice, setting out what steps they are taking to ensure that they meet the duty of care -- including by designing products and platforms to make them safer, and pointing users who have suffered harm towards support", the report says.

"The code of practice is also likely to include the steps companies will be expected to take to combat disinformation, including by using fact-checking services, particularly during election periods, and improving the transparency of political advertising. Regulated firms will be expected to comply with the code of practice -- or explain what other steps they are taking to meet the duty of care. However, many questions are left to the regulator to determine."