Britain’s Prime Minister David Cameron has announced that a joint UK-US task force is being formed to lead a global alliance with tech industry leaders, such as Google, Bing, and Yahoo, to stamp out online child pornography and pornographic images of rape that promote violence against women.

Beginning next year, existing fragmented database across all police forces will be combined to produce a single secure database of illegal images of children, which will help police to close the net on pedophiles, said Cameron. In addition, from the end of 2013, people will have to opt in to get pornography on their computers in the United Kingdom.

"When it comes to the Internet, in the balance between freedom and responsibility, we have neglected our responsibility to our children," Cameron said in a speech given in London early this morning. "My argument is that the Internet is not a sideline to 'real life' or an escape from 'real life'; it is real life."

He challenged Google, Bing, Yahoo, and the rest that they have a “duty to act” and it is their “moral duty” to give clear routes out of that search to legitimate sites on the website. “There should be a list of terms blacklist, which would offer up no direct search terms.”

“I simply don’t accept the argument that some of these companies have used to say that these searches should be allowed because of freedom of speech,” he said.

He warned internet giants they could face tough new laws if they fail to blacklist key search terms for vile images by this October. “If the answer is no or the progress is slow or non-existent, I can tell you we’re already looking at legislative actions so we can force action in this area.”

In a statement, a Google spokesman said: "We have a zero tolerance attitude to child sexual abuse imagery. Whenever we discover it, we respond quickly to remove and report it.

"We recently donated $5m (£3.28m) to help combat this problem and are committed to continuing the dialogue with the Government on these issues."

Meanwhile, Cameron’s plan would subject video streamed online in the UK to the same restrictions as those sold in shops. Possessing violent pornography showing simulated rape scenes will also be made a crime in England and Wales.

Internet service providers (ISPs) will introduce a "default on" filters that will oblige homeowners to "opt in" to receive sexually graphic material, meaning by 2014 all households will have their access to online pornography blocked unless they specifically request to keep it.