A group of British politicians want companies to pull advertising from firms that fail to tackle terrorism.

In a report, the U.K. Parliament's Intelligence and Security Committee concluded that security agencies needed help from the likes of Facebook, Twitter and Google to curb the "enormous growth" in online extremist material.

The report said, "There has been an enormous growth in the volume of extremist material that can be found online. Studies have shown that almost all attack planners between 2012 and 2017 have downloaded, shared or consumed radical and extremist media of some kind. However, the quantity of material and the ease with which it can be uploaded, versus the difficulty and time it takes to remove it, means that the authorities will always be ‘playing catch up’.

The committee said online communications service providers (CSPs) have made "little tangible progress over the last four years" to tackle the publication of that type of content.

The report said, "Action that affects the CSPs' profits clearly hits home harder than any sense of 'doing the right thing'. Encouraging companies who advertise on the CSPs' platforms to put pressure on the CSPs to remove extremist content — with the threat of pulling their adverts if they do not — will have more impact on the CSPs."