David Cameron: I'm ready for a 'big argument' over pornography with web firms "Let's be fair to the companies, there are some good things that they're doing - they're making public wi-fi safer, that's good; they're flashing up warnings, some of them, when people are searching for things that are wrong," he said. But there is this problem, yes, that some people are putting simply appalling terms into the internet in order to find illegal images of child abuse - and remember every one of these pictures is a crime scene - and they're getting results. I think it's wrong that they should get results and we need to have very, very strong conversations with those companies about saying 'No, you shouldn't provide results for some terms that are so depraved and disgusting I can't even say them on your show'. I think there's going to be a big argument there, and if we don't get what we need we'll have to look at legislation. Mr Cameron acknowledged that politicians have not done enough in the past to prevent the spread of indecent images. In terms of legal pornography, the Prime Minister said he also wanted to do more to stop children getting access to adult images online. "We need to do more on this as well, and I speak as a parent - I've got a nine-year-old, a seven-year-old, and a soon-to-be three-year-old," he said. I worry desperately about this and I know parents do. Because when we're offline, there are rules about what films you can see in a cinema, what age you have to be to buy alcohol or cigarettes or what have you; but on the internet, there aren't those rules so we need to help parents with control. Downing Street had wanted internet service providers (ISPs) to introduce "default on" filters that would oblige home owners to opt in to receive violent or sexually graphic material. However, the internet companies argue that this would encourage complacency among parents and Britain could be accused of censorship.