PORN could be automatically blocked from every computer in Britain under government plans to protect kids, it emerged today.
The radical move would force people to ask internet service providers (ISPs) to lift restrictions before they could log on to saucy sites.
Ministers hope the idea will stop children being exposed to sex at an early age.
Communications Minister Ed Vaizey revealed: "This is a very serious matter.
"I think it is very important that it's the ISPs that come up with solutions to protect children.
"I'm hoping they will get their acts together so we don't have to legislate, but we are keeping an eye on the situation and we will have a new communications bill in the next couple of years."
Mr Vaizey has summoned some of the UK's biggest broadband firms, including BT, Virgin Media and TalkTalk, to a meeting next month for talks.
He hopes they will agree to ditch the current "opt-out" system - where people have to turn on computer "parental controls" to block porn - in favour of the "opt-in" idea.
TalkTalk, which also operates Tiscali and Aol.co.uk, is launching a free service next year which will only give access to sites on a cinema-style rating system.
Parents can also choose to give the ISP a list of adult sites they want to view.
It comes after an operation by several ISPs to stop people accidentally viewing child porn online.
Campaigner Miranda Suit, of charity Safermedia, said: "In the past, internet porn was regarded as a moral issue or a matter of taste.
"Now it has become a mental health issue because we know the damage it is causing.
"We are seeing perverse sexual behaviour among children.
"Legislation is both justifiable and feasible."
TalkTalk executive director Andrew Heaney said: "If other companies aren't going to do it of their own volition, then maybe they should be leant on.
"Legislation is a sledgehammer but it could work."
A Virgin Media spokeswoman added: "We're able to block sites, so it would be possible to do the same on the internet.
"It is just a question of finding the right approach."