U.S. President George W. Bush has quietly signed a new National Space Policy that asserts his country's right to deny access to space to anyone "hostile to U.S. interests."

The document characterizes the role of U.S. space diplomacy largely in terms of persuading other nations to support U.S. policy, encourages private enterprise in space and emphasizes security issues.

"Freedom of action in space is as important to the United States as air power and sea power," the document, a revision of the U.S.'s previous space policy, asserts in its introduction.