As the Home Office prepares to publish a draft code of practice for part three of the Regulation of Investigatory Powers (RIP) Act due in June, a small band of privacy advocates are rushing to develop a tool capable of undermining it.

The RIP Act proposes to give the government the right to demand the plain text and/or encryption keys for any "information protected by encryption".

Last week, Peter Fairbrother, head of the design team at m-o-o-t, an "open-design, open-source cryptography project", said that the toolkit is "undergoing a fundamental design review" to make it ready for release on the same day RIP three is announced.

The team said that m-o-o-t has been built "to allow UK citizens to communicate and to store information without worrying about it", but that it will also defeat the FBI's Carnivore system as well as laws put forward by Australia, New Zealand and the Council of Europe.

The product will consist of an operating system which boots and runs only from the CD, with an application suite including email client, word processor, spreadsheet, graphics utilities etc.

Access to local storage such as hard drives and floppy disks will be disabled, and the system will shut down if the CD is removed.

All data, documents and mail will be transmitted over a secure internet connection and stored in encrypted form at off-shore data havens outside the UK's jurisdiction.

Files could even be split between different data havens, so that if one is compromised, the data is not.

Communication will only be possible between other m-o-o-t users with a single-use encryption key. Master keys will be kept on a remote server and secured using a steganographic file system.

This includes intercepted communications, information on hard discs in PCs, and information stored on servers, as well as PGP/RSA private keys.

"We are doing this so people can be private elsewhere than in our heads. We object to the idea that people should not be allowed to seek privacy from governments," said Fairbrother.

But as New Scientist reported that a version of m-o-o-t should be ready for testing in the next two weeks, and the final product ought to be ready for the introduction of RIP three, the Home Office got on its high horse and condemned the project as a criminal tool.

"Such a device in the wrong hands will do far more to infringe the human rights of innumerable potential victims than a regulated and inspected process such as RIP could ever allow," the Home Office was quoted as saying.