US President George W. Bush has signed a presidential directive on biodefense to help protect the country from biological attacks, the government announced Wednesday.

The directive, approved by the president last week, was jointly announced by the Department of Homeland Security, the Department of Health and Human Services and the Defense Department.

"Defending against biological weapons attacks requires us to further sharpen our policy, coordination and planning," said the directive, which is aimed at coordinating efforts by government departments and agencies against biological threats.

Biological weapons attacks could cause catastrophic harm, and could inflict widespread injury and result in massive casualties and economic disruption, an unclassified version of the directive said.

Speaking at a news conference on Wednesday, Homeland Security Secretary Tom Ridge said that from the creation of a biological attack warning system to an improved distribution system of critical antibiotics and vaccines, the plan "charts the course toward our goal of a strong and robust bioterrorism defense."

The directive listed 59 instructions for government agencies, ranging from figuring out the best way to communicate the warning to analyzing intelligence from unrelated sources.

Source: Xinhua