London, Nov 4 (PTI): US technology companies have become the command and control networks of choice for terrorists and criminals, one of Britain's senior-most intelligence chiefs has warned and sought their cooperation in intelligence matters to tackle the menace.

Robert Hannigan, who recently took over as director of the UK's Government Communications Headquarters (GCHQ) – also referred to as Britain's listening post – warned that some US tech companies are "in denial" about how their services are being misused.

"However much they may dislike it, [US technology companies] have become the command and control networks of choice for terrorists and criminals, who find their services as transformational as the rest of us," he writes in an article for 'The Financial Times' today.

"The challenge to governments and their intelligence agencies is huge – and it can only be met with greater cooperation from technology companies. GCHQ and its sister agencies, MI5 and the Secret Intelligence Service, cannot tackle these challenges at scale without greater support from the private sector, including the largest US technology companies which dominate the web," he adds.

In his first public intervention, Hannigan argues that the big internet firms must work more closely with the intelligence services, warning that "privacy has never been an absolute right".

He goes on to say that Islamic State (IS), also known as ISIL, has a different approach to using the internet than other extremist groups have had.

"Where Al Qaeda and its affiliates saw the internet as a place to disseminate material anonymously or meet in 'dark spaces', ISIS has embraced the web as a noisy channel to promote itself, intimidate people, and radicalise new recruits," he says.

The debate about whether security agencies should be allowed to access personal data through social-networking sites like Google and Facebook was brought to the fore in 2013 after Edward Snowden leaked details of alleged internet and phone surveillance by US intelligence.

Snowden, who has been granted temporary asylum in Russia, faces espionage charges over his actions.

Hannigan, who has advised the British Prime Minister on counter-terrorism strategies in the past, calls for a "new deal" between democratic governments and the technology companies in the area of protecting citizens.

"It should be a deal rooted in the democratic values we share. That means addressing some uncomfortable truths. Better to do it now than in the aftermath of greater violence," he says.