Britain is to establish a dedicated team of computer experts to defend the country against cyber attacks.

The “cyber forensics” squad will monitor, analyse and counter hostile computer-based assaults.

Based at GCHQ, the Government’s communications network at Cheltenham, the Cyber Security Operations Centre is part of a new government strategy on cyber security.

Lord West, the Security Minister, admitted that Britain already has its own online attack capability. “It would be silly to say that we don’t have any capability to do offensive work from Cheltenham and I don’t think I should say any more than that.”

He said terrorist groups, including al-Qaeda, are intent on using the internet to launch cyber-warfare attacks against Britain and key parts of national infrastructure. Business, government and individual citizens are all at risk from attack.

Lord West said terrorists are already using the internet to recruit and communicate but are seeking to turn it into a weapon. He said foreign states and organised criminal gangs are also using cyber attacks against Britain with targets including Whitehall departments and financial markets.

Lord West was speaking as the Prime Minister published the Government’s cyber security strategy intended to counter the threat of attacks on computers and modern communications technology.

The document was released with an updated version of the National Security Strategy which takes into account the effects of the global economic downturn.

Lord West said the terrorists’ capability to launch attacks is something he believed “will develop” in future.

“We know terrorists use the internet for radicalisation and things like that at the moment, but there is a fear they will move down that path (of cyber attacks).”

But Lord West indicated that at present the greatest threat came from foreign states, followed by organised criminals and then terrorists. He said: “So far the terrorists have not been the biggest threat but they are learning quickly. There are state actors who do things and behind them serious criminals who are getting cleverer and cleverer at these attacks.”

He confirmed that the British Government has already faced cyber attacks from foreign states including Russia and China. But he insisted that hackers had not successfully broken into government systems or stolen secret information.

Officials declined to indicate how many attacks on government computer networks take place each day.They said they were not aware of any “key pieces of information” that had gone missing but said that British companies had lost critical information.

In America, President Obama has begun to place greater emphasis on defending computer networks. Whitehall officials said the two countries were co-ordinating closely not least because of the close relationship between GCHQ and its US equivalent.

A Whitehall official said: “In a sense cyber security strategy is the safety net to try to make sure a future digital Britain can operate securely and safely and in a resilient way.”

The official said the strategy was of huge importance because critical national infrastructure is dependent on cyber space in a way it was not five years ago.