Google and Twitter have rejected calls by a UK parliamentary committee to introduce measures to stop users breaking privacy injunctions, saying it would be impossible to censor content effectively.

The cross-party select committee of MPs and peers said in a report that the government should consider introducing legislation that would force Google to censor its search results to block material that a court has found to be in breach of someone's privacy.

“Requiring search engines to screen the content of their web pages would be like asking phone companies to listen in on every call made across their networks for potentially suspicious activity,” Google said on Tuesday.

However, the company said it already removes specific pages deemed unlawful by the courts and provides a number of simple tools anyone can use to report such content.

Twitter said it would continue to operate its current system of evaluating legal requests to remove material on a case-by-case basis.

Facebook said it was still reviewing the report by the cross-party committee set up by the prime minister in May last year to examine privacy and free speech after the controversy over the increasing use of so-called "super-injunctions" like the one taken out by footballer Ryan Giggs.

Requiring search engines to screen the content of their web pages would be like asking phone companies to listen in on every call made across their networks for potentially suspicious activity Google

Although the Manchester United footballer had taken out a super-injunction to prevent the newspapers from reporting allegations that he had an extramarital affair with model Imogen Thomas, details of the injunction and the alleged affair were widely reported on social networking sites.

The committee said on Tuesday that new privacy laws were not necessary, but called for an enhanced press regulator, with powers to fine newspapers. It also singled out internet companies for criticism, according to the Financial Times.

The committee said internet companies, such as Google, Facebook and Twitter, had presented numerous challenges to the rule of law in the UK.

Google argued that it would be difficult to put in place a mechanism to identify banned pictures or words, and that such a system could threaten the unfettered flow of information online. But the committee said Google’s arguments were “totally unconvincing”.

The government must respond to a select committee report within 60 days of publication and publish its response. However, it is not obliged to take the matter further or enact legislation.