US space agency NASA on Wednesday postponed the launch of the space shuttle Endeavour after technicians detected a hydrogen gas leak during fuelling just hours before scheduled lift-off.

The shuttle's launch had been set for 5.40 am (0940 GMT) from Cape Canaveral, Florida for a 16-day mission to the International Space Station (ISS). It was to carry the final pieces to the Japanese Kibo module of the ISS.