Satellite tracking of paedophiles is among a number of high-tech measures to protect children being proposed by the Conservatives.

The country's paedophile laws have come under fresh scrutiny following a wave of national concern over the murders of Holly Wells and Jessica Chapman.

And the arrest of two police officers involved in the Soham case on charges relating to internet child pornography have added weight to calls for tough new controls on the web.

Oliver Letwin and Tory home affairs frontbencher, Dominic Grieve, have published a policy paper centred around six measures to "strengthen paedophile laws".

Taking a space age approach to monitoring sex offenders believed to pose a risk to children, the Tories are arguing for the use of satellite positioning technology to track paedophiles.

"There is technology now available which would enable us to track where a particular individual is and there is also a law which enables judges to ban convicted paedophiles once released from going...near to a school," Letwin told the BBC.

"It may be that we could use this technology to automatically alert the police if the person in question, who had been banned from going near that school, went to it."

Satellite technology is already used in the US to track sex offenders, using ankle bracelets similar to the electronic tagging already in use in the UK.

Florida trials show GPS tracking to be three or four times more effective than other supervision and surveillance techniques.

American research found the rate of sex offender absconding after two years lowest for satellite tracking, 1.5 per cent, compared to community control, 3.5 per cent and radio frequency monitoring 4.6 per cent.

Letwin acknowledged that surveillance must remain targeted at offenders and not spread to general monitoring.

"One would need to hedge it about very, very carefully to make sure that it isn't the thin end of a wedge where we are all tracked every moment of our lives."

He is also urging special "psychometric" testing for everyone seeking work in children's homes and boarding schools.

This would involve questionnaires aimed at detecting paedophiles, or those predisposed to sex offending, who had not yet been caught up in the criminal justice system.

"Paedophiles tend towards a typical profile and the assessment is based upon historical variables and patterns of adult relationships. Some will of course have a pattern even though they may have no previous convictions, but where children's protection is involved, it is better to be safe than sorry," said Letwin.

One proposal previously highlighted by the shadow home secretary is a new criminal offence of "internet grooming".

Letwin backs new laws banning the grooming of children in internet chatrooms by predatory adults.

Conservatives believe it is "quite possible to draft a clause which would stop any action by an adult towards a child for harmful sexual purposes".

A Home Office taskforce is currently examining a shake up of sex laws and measures to crackdown on internet child abuse.

Many warn legislation could be unworkable and have cautioned ministers against rushing into "dangerous dogs"-style knee-jerk legislation.

The Tories believe that progress has been too slow. "The reason that we have been looking at these matters ourselves is that that taskforce has been fairly slow," said Letwin.

"No doubt there are issues here of huge complexity that need a long look, some of the enforcement issues for example, but some things can be done quite quickly and what we are trying to do is to precipitate action."

Letwin also urged tougher action against suspected internet child pornography.

"There is an increasing use of IT and the internet to store and distribute child pornography. This, when found, has been used as evidence against paedophiles," he said.

Police are often unable to break cheap encryption software - available online - and used by paedophiles. Unless suspects hand over the computer codes allowing the authorities to decode images, Letwin believes, they should be treated as guilty.

"Our proposal is that the sentence for failure to provide the key where the encrypted information is seized under the Child Protection Act should match that which the accused would receive if the anticipated evidence were revealed."

But the Tories have ditched one anti-paedophile proposal suggested by the Conservative leader last month.

Iain Duncan Smith urged that judges be made to view child porn before sentencing offenders. "The full horror of this material should be seen and acknowledged," he said.