The national biometric identity card programme should be suspended until security fears have been eliminated, according to a group of academics.

The open letter to Andrew Dismore, Chair of the Joint Committee on Human Rights, refutes chancellor Alistair Darling's statement that the scheme will increase protection against identity fraud.

"These assertions are based on a fairy-tale view of the capabilities of the technology, and in addition, only deal with one aspect of the problems that this type of data breach causes," it says.

Signatories of the letter include Ross Anderson, professor in Security Engineering at the University of Cambridge Computer Laboratory, Richard Clayton from the same department - who advised the House of Lords Inquiry into Personal Internet Security, and former Ministry of Defence and Nato employee Brian Gladman.

The academics assert that the chancellor's assertion is only true on three conditions.

First, that the entire population can be successfully biometrically enrolled onto the National Identity Register (NIR), and successfully matched on every occasion thereafter.

Second that biometrics are unforgeable.

Third that every ID check will be authenticated by a live biometric check against the biometric stored on the NIR.

All three criteria are unlikely to be met, according to the letter.

According to the Home Office, an ID card will link a person securely and reliably to their identity. Increased penalties of up to 10 years for tampering with the NIR will also help security, it says.