Senior managers have decided that the aging fleet of reusable spacecraft is safe to resume flights to the International Space Station.

A flight readiness review by NASA executives and engineers decided on the repairs and improvements to shuttle systems, after the destruction on re-entry of the Space Shuttle Columbia in 2003 and further safety problems found in the course of a July 2005 shuttle flight.

The remaining US shuttles have been grounded since the Columbia disaster, except for last year's single launch.

In a statement issued from the Kennedy Space Centre at Cape Canaveral, Florida, NASA chief Michael Griffin said Saturday that the two-day consultations that produced the "go" decision were "spirited and one of the most open, yet non-adversarial meetings I've seen since returning to NASA".

Shuttle Commander Steve Lindsey is to lead a six-member crew on a scheduled 12-day mission. European Space Agency astronaut Thomas Reiter will be delivered to the International Space Station, joining two astronauts already in orbit since March.

Part of the mission will be used to evaluate new safety measures.

Foam insulation on the external shuttle fuel tanks have been a source of numerous problems, including the Columbia disaster and serious safety issues with last year's flight.

--DPA