The European Commission has outlined how firms like Google, Facebook and Twitter should remove illegal content more quickly from the web, increasing pressure on the companies to do more.
The spread of illegal content on the web, whether because it infringes copyright, involves counterfeit goods or contains threatening material, has sparked a heated debate in Europe between those who want online media firms to do more to tackle it and those who fear it could impinge on free speech.
As a result the Commission has issued a set of guidelines for how the internet firms could increase the speed and effectiveness of their removals of content, be it through establishing trusted flaggers or investing more in automatic detection technologies.
"The rule of law applies online just as much as offline. We cannot accept a digital Wild West, and we must act" - EU Justice Commissioner Vera Jourova.
The companies have recently stepped up efforts to tackle the problem, agreeing to an EU code of conduct to remove hate speech within 24 hours and forming a global working group to combine their efforts in removing illegal content from their platforms.
But the Commission said the companies were still too slow.
"The situation is not sustainable: in more than 28% of cases, it takes more than one week for online platforms to take down illegal content," said Mariya Gabriel, EU digital commissioner.
The guidelines call on the companies to appoint points of contact so they can be rapidly alerted about illegal content and work with trusted flaggers – experts in identifying such content.
Existing EU legislation says internet platforms should not be liable for the content that is posted on their websites by users, limiting how far policymakers can force companies, who are not required to actively monitor what goes online, to act.
Illegal content should be removed as quickly as possible and can be subject to specific time frames, the Commission said, and automatic tools should be used to prevent previously removed content from being uploaded again.
The Commission said it would monitor companies' progress and could come forward with legislation by next Spring if it is not satisfied.
The Computer and Communications Industry Association (CCIA), which represents companies like Google, Amazon and Facebook, welcomed the Commission's guidelines.
"CCIA has advocated for a long time for the introduction of well-thought-out notice and action guidelines, and this ... is a welcome initiative for a more aligned approach on the removal of infringing content across the European Union," it said in a statement.
However some politicians criticised the Commission's call for more automatic detection technologies, saying it would restrict the flow of information online.