A new National Cyber Force (NCF) will combine intelligence and defence agencies to protect the UK from online attacks.

The Prime Minister publicly avowed the new organisation in a speech to Parliament on Thursday on defence spending, although it is unlikely the NCF will seek any public profile in the future.

The new agency, led jointly by GCHQ and MoD but with representation also from MI6, will seek to disrupt terrorists, hostile state activities and criminals targeting the UK.

Typical cyber operations could include interfering with mobile phones or cell towers to prevent communication between known terrorists and destroying servers hosting material deemed a risk to national security. 

The NCF will also protect UK military hardware, such as the F-35 stealth fighter, from targeting by hostile weapon systems. 

Jerremy Fleming, the GCHQ Director, said: “For over a century GCHQ has worked to keep the UK safe. Cyber security has become an integral part of this mission as we strive to make the UK the safest place to live and do business online.

“Today the National Cyber Force builds out from that position of defensive strength. 

It brings together intelligence and defence capabilities to transform the UK’s ability to contest adversaries in cyber space, to protect the country, its people and our way of life.”

Around 3,000 cyber experts will be recruited over the next decade with staff being drawn from existing Defence or GCHQ employees.

MI6 will provide expertise in recruiting and running agents online. 

With the remit to target threats ranging from serious crime to state-based cyber attacks, exact boundaries between the NCF and existing bodies such as GCHQ and the National Crime Agency have yet to be worked out.

A source told the Telegraph it is likely the other government agencies will be responsible for collecting intelligence, handing over to the NCF for “executive action”. 

In recent months applicants for the NCF from the armed forces have been undergoing aptitude and attitude tests, following which they have been streamed into different roles.

The Telegraph understands the NCF has had more applications from military personnel than posts to fill.

Defence Secretary Ben Wallace said the NCF is “bolstering our global presence in the cyber domain”. 

“It is a clear example of how we are turning our ambitious agenda to modernise defence into a reality.”

The MoD has been seeking for some time to adjust terms and conditions of military service to allow some cyber experts, who may not meet age or fitness criteria, to continue to serve.

The new agency will initially be based out of existing GCHQ and MoD locations in Cheltenham, London and Porton Down, but is expected to seek move into its own premises in the near future.