The Prime Minister is to announce a Government-backed code-of-conduct which will mean pornography is blocked in any public place where children are likely to be present.



The plan to impose a ban where children are likely to be present follows high-profile campaigning by children's charities for a complete block on unacceptable sites in public areas.



Mr Cameron has insisted that the Government has a responsibility to provide "good clean Wi-fi" in public areas.



"We are promoting good clean Wi-fi in local cafes and elsewhere to make sure that people have confidence in public Wi-fi systems so that they not going to see things they shouldn't," he said, speaking to the Telegraph.



The coalition has already backed moves to introduce other web controls.



It is not yet clear whether restrictions will be enforced by the Internet service providers or though individual cafes and other public places.