The Government should seriously consider retaining controversial control orders to keep tabs on suspected terrorists, a think-tank has said.
The orders, while flawed and of only limited effectiveness, "perform an important function imperfectly" and not all terrorist threats can be tackled in the courts, the Centre for Social Cohesion (CSC) said.
It said the Government, which is reviewing its counter-terrorism strategy, "should seriously consider retaining the system while robustly addressing its deficiencies".
Critics of the orders, including human rights group Amnesty International, have accused the UK of operating a "secretive shadow justice system" for terror suspects which campaigners say must end.
But Robin Simcox, CSC research fellow and the report's author, said: "Members of the Government have called for the abolition of control orders but offered no viable alternative.
"No-one is saying control orders are perfect, but they are the best option available with the law as it stands. Not all terrorist threats can be dealt with in the preferred manner of convictions in British courts."
On the eve of the ninth anniversary of the September 11 terror attacks in New York, he went on: "The threat from al Qaida-inspired terrorism remains high, and those under control order have often been committed jihadists. Control orders help contain this national security threat."
A total of 45 individuals were subject to control orders at some point between their launch in 2005 and December last year, the report, Control Orders: Strengthening National Security, found.
Only 12 of these were in force as of the end of last year. More than half of these (26) entered the UK seeking asylum, at least a fifth (nine) were British citizens and more than one in six (seven) have absconded.
In July, the Court of Appeal paved the way for terror suspects to sue for damages over legally-flawed control orders which breached human rights.