The government has allocated approximately £500 million to tackle internet threats.

This afternoon it published a National Security Strategy, highlighting the severe risk to the UK of cyber warfare.

The document did not confirm plans for tackling the problem or the exact funding available, but instead set the context for tomorrow's Strategic Defence Review - in which more details will be published.

Calling cyber warfare "one of the highest priority national security risks to the UK", the government promised it will also develop over time a more detailed "transformative programme for cyber security". The programme will address threats "from states, criminals and terrorists".

Cybercrime is detailed as a 'tier one' risk to Britain, alongside terrorism, international crises and natural hazards. The country's Office of Cyber Security, created when the coalition government came to power, will create the strategy and assess the risks, while a cyber security operations centre will take action to tackle the problems and be a central point for businesses and individuals to report concerns.

The strategy document singles out the 2012 London Olympics as being a "huge vulnerability" and at serious risk of cyber attacks from people attempting to "defraud and possibly disrupt". During the Beijing Olympics, it said, China received over 12 million cyber attacks a day.

"While cyberspace provides the UK with massive opportunities, the risks emanating from our growing dependence on it are huge," says the National Security Strategy. "By 2015, there will be more interconnected devices on the planet than humans - everything from mobile phones, cars and fridges will be networked across homes, offices and classrooms across the globe."

It added that activity in cyberspace "will continue to evolve as a direct national security and economic threat", used by spies, criminals, terrorists and potentially by rogue states.