The government's identity card and biometric passport scheme faces new criticism after a computer hacker revealed he has been able to copy the identity documents.

Speaking at the Defcon security conference in Las Vegas, security consultant Lukas Grunwald said he had discovered a method for cloning the information stored in the new passports.

The revelation casts another shadow over the government's plan for a national ID card, which would contain much of the same information.

The Home Office said yesterday that the UK biometric passport was one of the most secure in the world and while it might be possible to copy the chip data it was not possible to modify or manipulate any of the data.