Britons who have fought for Isis should never be allowed to come back to this country, the Defence Secretary has said.

Gavin Williamson said those who were intent on bringing "destruction, death and bloodshed" onto the streets of Britain were being "hunted down" and that threat "eliminated".

He told the Daily Mail: "A dead terrorist can't cause any harm to Britain."

In October, the terror laws watchdog said authorities should look to "reintegrate" the "young" and "naive" jihadis who travel to warzones, rather than prosecute them, on their return to the country.

Max Hill QC, the Independent Reviewer of Terrorism Legislation, spoke of "losing a generation" of men and women by automatically using the courts to punish them.

But Mr Williamson said the armed forces were working "right across the globe" to ensure jihadis are never able to come back to the country in the first place.

He said: "I do not believe that any terrorist, whether they come from this country or any other, should ever be allowed back into this country."

Mr Williamson told the paper the role of jihadis in foreign fields should not be underestimated, with "much of what is done to activate" threats to Britain done in places such as Libya, Iraq and Syria.

He added: "Our job in terms of eliminating will not stop this year, will not stop next year, it is something we have got to continue to pursue."

Hundreds of British citizens are known to have travelled to Syria to fight with Islamist groups during the course of the six-year conflict.

Meanwhile, Foreign Secretary Boris Johnson is due to deliver a speech on Thursday in which he will praise British efforts around the world to tackle terrorism.

He will say: "Every day around the world I can tell you that British serving men and women are putting their lives at risk to roll up terrorist networks, to expose what they are doing, to thwart them and bring them to justice.

Syrian Democratic Forces take Raqqa from Isis – in pictures Show all 8 1 /8 Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces fighters celebrate victory in Raqqa atop of military vehicles REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Fighters of Syrian Democratic Forces march past destroyed buildings as they celebrate victory REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Fighters of Syrian Democratic Forces gesture the "V" sign in Raqqa REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Fighters of Syrian Democratic Forces evacuate a civilian from the stadium REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures A civilian prays after she was rescued by fighters of Syrian Democratic Forces from the stadium REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces fighters ride atop of military vehicles as they celebrate victory in Raqqa REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces fighters celebrate victory in Raqqa REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures A fighter of Syrian Democratic Forces celebrates in Raqqa Reuters

"They are making good on what the Prime Minister has rightly called the unconditional commitment of the British people to the security of our European friends, not just in this continent but beyond."

On Tuesday, the director general of MI5 told the Cabinet that a total of nine Islamist terrorist plots have been thwarted in the UK over the past year.