Internet giants could be penalised through taxes if they fail to cooperate with Government efforts to fight terrorism and tackle online extremism, a minister has said.
Ben Wallace warned Britain is the most vulnerable it has been for 100 years due to terrorism fuelled by radicalising content online and "patience is running out fast" with web companies that put profit before public safety.
Obstruction and inaction by social media companies, whether it is by blocking access to encrypted messages or leaving extremist content on their sites, is costing taxpayers hundreds of millions of pounds, the Minister of State for Security said.
He said "ruthless profiteers" will not "get away" with leaving police and law enforcement to repair the damage done by radicalising content and revealed tax measures are being considered as a means to make them cooperate.
"Because of encryption and because of radicalisation, the cost of that is heaped on law enforcement agencies," Mr Wallace told the Sunday Times.
"I have to have more human surveillance. It's costing hundreds of millions of pounds. If they (internet firms) continue to be less than co-operative, we should look at things like tax as a way of incentivis-ing them or compen-sating for their inaction.
"Because content is not taken down as quickly as they could do, we're having to de-radicalise people who have been radicalised. That's costing millions. They (the firms) can't get away with that and we should look at all options, including tax."
Such a tax would be similar to the windfall tax imposed on excess profits of privatised utilities by the Blair government in 1997, or the levy Margaret Thatcher's government placed on banks in 1981, the newspaper said.
While internet companies have taken steps to tackle child abuse online, they "don't seem to be making the same effort" against extremism, Mr Wallace said.
Mr Wallace's warning comes after a parliamentary inquiry into fake news criticised Twitter and Facebook for failing to properly act against Russian attempts to influence British politics.
MP Damian Collins, chairman of the House of Commons Digital, Culture, Media and Sport Select Committee, said Facebook had appeared to have done "no work" to fully root out accounts that could be linked to Russian-backed agencies during the EU referendum.
Meanwhile Twitter was condemned by the committee for a "completely inadequate" response to the investigation.
Senior executives from Twitter, Facebook and Google, which owns YouTube, were accused of profiting from violence and criticised for failing to remove offensive content when they appeared before MPs in December.
Yvette Cooper, chair of the Home Affairs Select Committee, urged the companies to accelerate efforts to tackle hate crime after a number of MPs were subject to abuse online.
Labour has suggested social media companies should face "punitive" fines for failing to react quickly to offensive material that incites hatred and violence.
In June, Facebook, Microsoft, YouTube and Twitter formed the Global Internet Forum to Counter Terrorism to address the "critical challenge" posed by the spread of terrorism online.
Google has announced it will "significantly" increase the number of staff tracking down extremist, violent and predatory content posted on YouTube to more than 10,000 in 2018.