The US space agency was readying the space shuttle Atlantis and its crew of seven astronauts for a Monday launch to deliver a load of spare parts to the International Space Station (ISS).

Liftoff is set for 2.28pm (6.28pm GMT) from the Kennedy Space Centre near Florida's Cape Canaveral, NASA said on Saturday.

"Atlantis is ready to go, in really great shape," said shuttle launch manager Mike Moses at a press conference broadcast on NASA television.

"We're right on the money," added Mike Leinbach, space shuttle launch director. "We're not tracking any issues with the vehicle, flight elements or ground systems. I'm happy to report we're ready to go."

Chief launch meteorologist Kathy Winters also confirmed that "weather should be very good" at Kennedy Space Centre on Monday, and said there was just a ten-percent chance of weather prohibiting the launch.

Weather conditions were also favorable at two of the three emergency landing sites in Europe where the shuttle would head if the mission were to be aborted after it was too far for a return glide to Cape Canaveral.

Final mission for 2009

The three-hour procedure of fuelling the shuttle's huge external tank with liquid hydrogen and oxygen is due to start at 5am.

Led by Marine Corps colonel Charlie Hobaugh, the all-male crew arrived Thursday at Kennedy Space Centre from Houston, Texas, where the astronauts are based. They will wake at 4.30am and board the shuttle at 11.08am.

The 11-day space outing, to be the fifth and last shuttle mission for 2009, is set to include three spacewalks aimed at storing space hardware on the exterior of the ISS.

The delivery of spare parts to the orbiting outpost is designed to keep the orbiting outpost in service after the shuttle fleet is retired.

Atlantis will also bring back US astronaut Nicole Scott, who has served as flight engineer on the ISS since August.

There are just five more shuttle launches scheduled before the planned September 2010 retirement of the fleet.

Going spare

"This flight is all about spares ? basically, we're getting them up there while we still can," Brian Smith, space station flight director for the 0mission, said in a statement released by NASA.

"You'll see this theme in some of the flights that are going to come after ours as well," Smith added.

In total, NASA said some 27 250 pounds of spares will be delivered ? including two gyroscopes, used in manoeuvring the station.

The White House could still decide to extend the program through 2011 to reduce US reliance on Russia's Soyuz craft for astronaut transport to the ISS while the future Orion capsules are being built.