The cyber-warfare guidelines will apparently create rules under which the US would "penetrate and disrupt" foreign computer systems.
The directive for the guidelines, which will be similar to the doctrine which has regulated the use of nuclear weapons since the second World War, was signed in July 2002 but was first publicly disclosed last week.
It is reported that although the US has never conducted a large-scale strategic cyber-attack at national level, the Pentagon is now considering the possibility of invading enemy computer networks to shut down radars and disable electrical facilities and telecommunications.
The cyber-warfare rules are reportedly being prepared amid speculation that the Pentagon is considering network attacks against Iraq, should the US decide to go to war over Baghdad's weapons' programmes.
The Washington Post reports that the cyber-warfare guidelines have been the subject of lengthy negotiations involving the Pentagon, CIA, FBI and National Security Agency, however, a number of issues "remain far from resolved" and the President's directive is "just an initial step".