The SAS – Britain’s elite fighting force – has been given free rein by Prime Minister David Cameron to take out ISIS leadership in Syria and Iraq. It is expected that 60 – 100 troops, working alongside intelligence agencies MI6 and GCHQ, will conduct increasingly proactive missions against Islamic terrorist cells.

Special forces began to be deployed early in June, but their fresh orders from David Cameron are thought to be the start of the “full spectrum” of responses he pledged after ISIS murdered 30 Britons on a Tunisian beach one week ago.

A senior intelligence source told The Sunday Times of the plan: He said:

“The SAS have been pushing to be more proactive for quite a while.

“In the past couple of years they have planned a number of operations in Syria when the chemical weapon threat was high but the missions were vetoed at the highest level because of the risks involved.

“The Tunisian attack has led to a rethink and has speeded up the inevitable use of SF [special forces] against Islamic State.”

The new “proactive” missions will involve identification of targets for air strikes in Iraq and Syria, battle damage assessment and striking “high value targets” including top ranking members of ISIS. Special forces could be sent anywhere, but are only likely to be operational in Iraq, Syria and North Africa. The elite British troops will work alongside US Delta Force and Navy Seal teams.

US Special Forces carried out a raid in Syria in May that killed Abu Sayyaf, a top Isis commander, capturing his wife and a rescuing a Yazidi sex slave.

On the 5th of June it was reported that a new British fighting group had been formed to operate alongside US Special Forces in Iraq and Syria; collecting intelligence and potentially rescue hostages. It incorporated personnel from the Parachute Regiment, Commandos and members of the RAF.

The re-organization included the formation of a new intelligence unit, called the Special Reconnaissance Regiment, set up earlier in the year in Hereford alongside the SAS base there.

Defense Secretary Michael Fallon revealed last week that ministers were debating bombing raids against ISIS strongholds in Iraq, as well as Syria now – possibly as early as September.

He said it was “illogical” to bomb ISIS on only one side of a border that they did not even recognise.