Lolita C. Baldor, AP Writer

WASHINGTON (AP) -- Defense Secretary Robert Gates formally ordered the creation Tuesday of a new military cyber command that will coordinate the Pentagon's efforts to defend its networks and conduct cyberwarfare.

A three-page memo signed by Gates orders U.S. Strategic Command to begin plans to set up a subcommand and be prepared to provide an implementation plan by Sept. 1, and begin initial operation no later than October.

"Our increasing dependency on cyberspace, alongside a growing array of cyber threats and vulnerabilities, adds a new element of risk to our national security," said Gates in the memo, which was obtained by The Associated Press.

He added that the new command "must be capable of synchronizing warfighting effects across the global security environment as well as providing support to civil authorities and international partners."

The low-key launch of the new military unit reflects the Pentagon's fear that the military might be seen as taking control over the nation's computer networks.

Creation of the command, said Deputy Defense Secretary William Lynn at a recent meeting of cyber experts, "will not represent the militarization of cyberspace."

Lynn said the focus of the command will be on the military's 15,000 networks and its seven million computers, noting that commanders depend on those systems in battle. The military, he said, needs to be able to respond to any intrusion or attack "at network speed."

Pentagon officials have stressed in recent weeks that the cyber command will not infringe on the Department of Homeland Security, which is the lead agency for other federal digital systems.

President Barack Obama has announced plans to name a cyber coordinator for the White House, in order to better coordinate the nation's efforts to protect critical computer networks and work more closely private industry, which owns or controls key financial, electrical and other systems.