He confirmed that people who refused to reveal encryption keys to police -- allowing them to read coded information -- could face a two-year jail sentence under the bill.

FORGETFULNESS NOT A CRIME

``The police have to prove the encryption key was deliberately witheld,'' the spokesman said.

``We're not talking about people going to prison for forgetting passwords.''

The bill had its second reading on Thursday in the House of Lords, Britain's upper chamber of parliament, and should go to a final reading in mid-June, the spokesman said.

Home Secretary Jack Straw introduced the bill earlier this year to a chorus of disapproval, mainly over its power to force Internet service providers (ISPs) to grant police access to a huge amount of information on internet users.

Civil liberties groups said the bill would make it far easier for police to access web surfers' personal and banking data, lists of websites visited, and even allow real-time monitoring of people's Internet activity.

But the Home Office insisted the bill gave no new powers to security services, and that they would need a special warrant to access information from ISPs.

``Interception of communications is only used on the authorisation of the Home Secretary himself,'' the Home Office spokesman said.

``And it's only used in defence of national security or on suspicion of serious crime, like narcotics smuggling or terrorism.''

He said about 2,000 warrants for communications interception were issued last year.

The government wanted the bill passed before October, the spokesman added, when British law is due to become fully compliant with the European Convention on Human Rights.