Ministers have been accused of failing to crack down on pornographic websites that can easily be viewed by children.

The claim came just days after the children's minister, Sarah Teather, unveiled the Bailey review into the sexualisation of children, which recommended that age ratings be introduced for raunchy pop videos and "vanity covers" be compulsory for so-called lads' mags such as Nuts and Zoo.

It emerged this weekend that the government has not acted on a separate recommendation from the media regulator, Ofcom, which said last year that the law should be changed so that sexually explicit content on video-on-demand websites could not be seen by children.

The government asked Ofcom last year to examine whether the law should be changed to protect children from pornographic material that was easily available on some adult sites, including Playboy.tv, which allowed paying members to download a wide range of pornographic material.

Many of them also offer sexually explicit "try before you buy" content that can be easily viewed without a credit card or account number.

Ofcom recommended in a report passed to the Department for Culture, Media and Sport (DCMS) nine months ago that the government should pass legislation forcing those sites to protect their free trial content with a pin number. But the coalition has not published Ofcom's report or acted on its recommendations.

Ivan Lewis, the shadow culture secretary, said: "David Cameron's commitment to act on Bailey's recommendations rings hollow now we know his government has suppressed this important report. It is either incompetence or a deliberate attempt to keep the public and parliament in the dark. Ofcom's report should be published without delay so we can consider its findings and take the necessary action."

The DCMS said the report was still being considered by ministers. It said: "The government is committed to protecting children from accessing harmful material and DCMS has requested advice from Ofcom and others regarding regulation of video-on-demand services. There is a range of views on whether new measures are required and we are currently considering options."

Whitehall sources speculated that last year's Ofcom's recommendation, which the regulator said could be implemented through secondary legislation, might be a casualty of the government's war on red tape.It has made a commitment to introduce new regulations only when another is scrapped to make way for it, a "one in, one out" policy that made it difficult to implement some new proposals.

A wide-ranging EU directive on media services, enshrined in UK law two years ago, introduced new rules on the regulation of "TV-like content" online. The Audiovisual Media Services Directive was controversial because internet companies including YouTube, which is owned by Google, believed it could make them subject to the same regulations that govern terrestrial TV channels such as ITV and Channel 4.

That was ruled out by the EU, but the directive does include a requirement for member states to protect minors from adult content available on video-on-demand services by forcing them to introduce access codes. The proposals would only affect a handful of websites that are monitored by Atvod, which regulates editorial content on video-on-demand services.

The Bailey review was written by Reg Bailey, the chief executive of the Christian charity the Mothers' Union.

David Cameron is backing its key recommendations, which also include the creation of a new website where parents can complain about broadcasters or advertisers who use sexually explicit content.

Cameron raised the issue when he was in opposition, but the government needs to balance a desire to address parents' concerns against the need to ensure the music, entertainment and advertising businesses continue to grow.Taken together the creative industries, which also include fashion, design and video games, continue to expand despite the challenging economic environment.