In a statement, the Ministry of Defence (MoD) said it believes the UK is very well prepared and has a range of contingency plans in place.
"The UK Armed Forces and the equipment and assets they use are among the world's most modern and advanced, so of course information technology plays a vital role in their operation," said defence minister Andrew Murrison.
"Far from being complacent, the MoD takes the protection of our systems extremely seriously and has a range of contingency plans in place to defend against increasingly sophisticated attacks.
"The level of government funding to tackle this threat underlines the importance we attach to these issues."
Martin Sutherland, managing director of BAE Systems Detica, said the report underlined the need to develop cross-government and private sector plans to tackle cyber threats.
"The UK's ability to defend itself against cyber attacks does not rest in the hands of any single entity. We need to encourage more organisations to share best-practice approaches to cyber security and provide more information about the nature of the attacks they're seeing," he said.
"Accordingly, much of the Government's Cyber Security Strategy focuses on enabling organisations to better defend themselves - for example, the creation of the ‘Cyber Security Guidance for Business' document and the recently launched Cyber Incident Response Scheme."
The Cyber Incident Response initiative designed to offer companies and public sector organisations assistance in the aftermath of cyber security attacks.
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