Washington  - Astronauts won't make it to the moon or Mars under the current budget for the US space programme, a panel reviewing manned spaceflight policies said Tuesday.

"The US human spaceflight programme appears to be on an unsustainable trajectory," the panel said in a summary of its findings. "It is perpetuating the perilous practice of pursuing goals that do not match allocated resources."

The panel of former astronauts and aerospace experts was formed by President Barack Obama with the task of examining all aspects of manned spaceflight, including the planned retirement of the US space shuttle fleet next year and existing plans to return humans to the moon by 2020.

A review of all options found that no future manned exploration - whether to the moon, Mars or elsewhere - could be accomplished under the current spending plan of about 9 billion dollars per year on exploration. At least 3 billion dollars more per year is needed to take astronauts out of low-Earth orbit, where they have been confined since the 1970s.

The report does not focus on many specific recommendations, instead presenting various options for phase out the ageing space shuttles, what to do with the International Space Station (ISS), how to get the next generation spacecraft into orbit, how to get astronauts into low-Earth orbit and where humans should travel next in space.

The panel did note that the space-shuttle programme will likely need to be extended into 2011 to complete the remaining six scheduled flights to the ISS.

Current plans call for the retirement of the shuttle by the end of next year, leaving astronauts dependent on Russia's rocket-mounted Soyuz space capsules for transport to the ISS and the scrapping of the station itself in 2016. The panel also recommended an extension of the ISS mission. (dpa)