A specially-armed US Navy warship is moving in to position in the Pacific to destroy an out-of-control satellite, using missiles originally designed to intercept ballistic missiles.

The launch could take place as soon as tonight, once the space shuttle Atlantis, currently in orbit after a mission to the international space station, has safely returned to Earth.

China and Russia have expressed concerns over the plan, saying that it represents a veiled weapons test and that it is the first step in a new, space-based phase of the arms race.

In preparation for the strike, the US government has issued a warning to air and sea traffic to remain clear of an area of the Pacific while the USS Lake Erie carries out its task.

US Defence Secretary Robert Gates has been granted the authority by President Bush to give the go-ahead to launch.

Washington has denied accusations that the interception is a show of strength after China's successful shooting down of a weather satellite in January 2007. It also denies that it is hiding technological secrets by destroying the satellite.

While the SM-3 interceptor missiles have successfully brought down ballistic missiles in tests, the bus-sized satellite represents a much greater problem.

It is colder, making it harder to track with the infrared "heat-seeking" technology, and is travelling far faster.

Full article here.