Tough new sentencing laws would see the most dangerous terrorist offenders jailed for a minimum of 14 years.
Under the Counter-Terrorism and Sentencing Bill, due to be introduced to Parliament on Wednesday, terrorists will also have to spend up to 25 years on licence after their release.
Those handed extended determinate sentences would have to serve their whole term in jail and would be denied early release.
This would apply to anyone found guilty of a terror offence where the maximum penalty is two years or more.
The bill will also seek to restrict the movements of suspected terrorists being monitored by security services indefinitely, while terrorists could also be made to take a lie detector test to prove they have reformed and are not planning another attack.
The proposals are among measures the government wants to introduce to disrupt terrorist activity and keep terrorists behind bars for longer.
Ministers have described the bill as the largest overhaul of terrorist sentencing and monitoring in decades.
But campaigners have warned it is a move to bring back controversial control orders “in all but name”.
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Control orders were introduced as part of 2005 anti-terrorism legislation. Signed by the home secretary, they put a suspect under close supervision, described by some as similar to house arrest, with restrictions on who they meet and where they go.
They were repealed and replaced with measures known as Tpims (Terrorism Prevention and Investigation Measures) in 2011, which the government said was a less intrusive system that addressed concerns about civil liberties, with time limits and a higher test to be met for one to be brought into force.
A Tpim notice can involve measures like an enforced curfew, tagging, living away from an address or area and restrictions on overseas travel.
They are seen as the strictest monitoring tool available for security services to use against people they believe to be involved in terrorism or who present a threat, but cannot be prosecuted or deported.
The changes could see courts allowed to renew Tpims indefinitely, subject to review, rather than lasting for a maximum of two years.
The bill also seeks to lower the standard of proof for imposing a Tpim, so 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”.
Justice secretary Robert Buckland said the government was “pursuing every option” to tackle terrorism, adding: “Terrorists and their hateful ideologies have no place on our streets.”
Home secretary Priti Patel said: “The shocking attacks at Fishmongers’ Hall and Streatham revealed serious flaws in the way terrorist offenders are dealt with.
“We promised to act and today we are delivering on that promise.”
However, the proposals have been condemned by human rights group Liberty, which said the presumption of innocence “hangs in the balance”.
Policy and campaigns officer Rosalind Comyn added: “This legislation not only authorises people being locked up indefinitely, it also poses a threat to fundamental pillars of our justice system…
“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.”
Shadow justice secretary David Lammy gave cautious support to the proposals, but said: “Labour will look in detail at the changes proposed in this bill. We will work constructively with the government on measures that reduce the chances of those who commit terrorist offences from reoffending.”