A Government adviser has accused China and Russia of carrying out cyber warfare attacks aimed at stealing national security secrets from other countries.
Baroness Neville-Jones, who is the Prime Minister's special representative to business on cyber security, said Beijing and Moscow were among the governments "interested in this kind of activity".
Her comments came on the eve of an international conference hosted by Foreign Secretary William Hague to discuss "norms of acceptable behaviour in cyberspace" which both countries are due to attend.
Earlier Iain Lobban, the head of Britain's electronic "listening" agency GCHQ, disclosed that the Foreign Office and other Government departments had faced a "significant" cyber attack on their computer systems over the summer. Mr Lobban, writing in The Times, did not say who was responsible for the attack and the Government has in the past been reluctant to point the finger of blame publicly at countries which it believes are engaged in such activity.
But pressed during an interview on BBC Radio 4's The World At One on whether China and Russia were among the countries involved in such attacks, Lady Neville Jones replied: "They certainly are."
Lady Neville-Jones, who was the security minister until last May, said countries needed to understand that such behaviour was actually counterproductive and would damage their own national interests.
"What we want to try and do is to create a climate in which people feel that obeying the rules and actually behaving above board serves the national interest and that it is damaging in the end to try to play both sides. Because if you are a company that comes from a country like China, you can suffer if people believe it is potentially threatening to employ your products," he said.
She said that such attacks were not only carried out by governments, but by individuals who then sold the secrets they had stolen to rival governments.
"There are a lot of private individuals who do this kind of 'hoovering' of other people's systems and then try and sell the stuff that they have managed to obtain to buyers. Those buyers can indeed be governments," she said.
Mr Lobban's disclosure of the latest attack on the Foreign Office computer system comes after Mr Hague revealed in February that it had been targeted by a "hostile state intelligence agency". Mr Hague did not name the country behind the attack, although media reports quoted intelligence sources as saying that China was responsible.