Court orders restricting the movements of suspected terrorists could be renewed indefinitely under new legislation unveiled by the government.
The bill would lower the standard of proof to impose the orders, known as TPims, and remove the current two-year limit that applies to them.
Suspects would also have to register all electronic devices at their home address.
But ministers have been challenged to justify the need for the changes.
The amendments are being proposed under the Counter Terrorism and Sentencing Bill, which aims to ensure the most serious offenders spend longer in prison.