Paedophiles are to undergo lie detector tests to see if they are likely to reoffend, the Home Office confirmed.
The system would see "trigger phrases" raising an alarm
Home Secretary John Reid had been seeking an amendment to legislation to approve the first trial of the lie detector tests.
It has been seen as an attempt to reassert his authority after two paedophiles were freed from prison.
The Home Office has confirmed the tests are in an amendment to the National Offender Management Services Bill.
Home Office revelations
"John Reid has agreed to include it as a government amendment. What this amendment will do is legislate for us to trial these tests," a Home Office spokeswoman said after a report in the Sunday Times.
Labour had originally planned compulsory lie detector tests for sex offenders in its 2005 general election manifesto.
Confirmation of the plan comes as the News of the World reported police forces across the UK have lost track of the whereabouts of 322 convicted sex offenders, a newspaper has reported.
The Home Office has also been dealing with the fallout of revelations it had failed to carry out proper checks on thousands of British offenders who had committed crimes overseas, and also allowed nearly 150 convicted drug traffickers to travel overseas.