The movement of terror suspects could be restricted indefinitely under new legislation being introduced later.
The Counter-Terrorism and Sentencing Bill has been described by ministers as the largest overhaul of terrorist sentencing and monitoring for decades.
In the wake of the London Bridge and Streatham terror attacks, the government wants to take further action to disrupt terrorist activity and keep terrorists behind bars for longer.
Home Secretary Priti Patel said those two “shocking” attacks had revealed “serious flaws in the way terrorist offenders are dealt with”.
“We promised to act and today we are delivering on that promise,” she said.
Labour’s shadow justice secretary David Lammy said the string of “horrific” attacks in recent years demonstrated that terrorism legislation needed to be updated.
He said: “We will work constructively with the government on measures that reduce the chances of those who commit terrorist offences from re-offending.
“Those who seek to terrorise our communities with savage acts of violence must be stopped.”
Campaigners have expressed concerns, however, warning the bill is an attempt to bring back controversial control orders “in all but name”.
These were introduced back in 2005 and had to be signed off by the home secretary.
Control orders put a suspect under close supervision, with restrictions enforced on who they could meet and where they could go.
They were likened to being under house arrest and were repealed in 2011.
Control orders were replaced by Terrorism Prevention and Investigation Measures (TPIMs).
The Conservative-Liberal Democrat coalition said it was a less intrusive system which addressed civil liberties concerns through time limits and a higher test needing to be met for one to be enacted.
A TPIM notice can include an enforced curfew, tagging, living away from an address or area and restrictions on overseas travel.
They are considered to be the strictest monitoring tool security services can use against people they think are involved in terrorism or present a threat, but who cannot be prosecuted or deported.
Under the legislation being tabled by the government, courts could be allowed to renew TPIMs indefinitely, subject to review, rather than lasting a maximum of two years.
Ministers also want to lower the standard of proof for imposing a TPIM.
The home secretary would need “reasonable grounds” for suspecting someone is, or has been, involved in terrorist activity, rather than basing the decision on the “balance of probabilities” which is currently the case.
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Officials say they are not expecting a surge in numbers if the legislation is passed.
They insist that TPIMs would still be subject to intense scrutiny.
According to the latest figures, around five are in force.
Rosalind Comyn, policy and campaigns officer for human rights group Liberty, said the new legislation “threatens all of our civil liberties”.
“This legislation not only authorises people being locked up indefinitely, it also poses a threat to fundamental pillars of our justice system,” she said.
“By reintroducing, in all but name, the widely condemned control orders, a fundamental principle of justice – the presumption of innocence – hangs in the balance.
“The fact this bill is being issued during a pandemic, when parliament is not operating at full capacity or able to deliver normal levels of scrutiny, should be a cause of concern for all who care about the future of our democracy and justice.”
Also included in the bill is a provision to bring in a 14-year jail term for the most dangerous offenders, who will also have to spend 25 years on licence after being released.
Terrorists given extended determinate sentences will be denied early release and will have to serve their whole term in prison.
This will apply to anyone convicted of a terror offence where the maximum penalty is two years or more in jail.
Another measure is the possibility of terrorists being made to take a lie detector test to prove they have reformed and are not planning another attack.
This has been criticised by opponents, who point out that the accuracy levels of such tests have been put as low as 60%.