India eagerly said it would join the plan; Japan and Europe -- frustrated junior partners in the US-led International Space Station (ISS) -- were somewhat guarded; and cash-strapped Russia proudly said it already had the knowhow to launch its own lunar and Martian missions.

There was no immediate official response from China, which catapulted itself into space's top division last year by becoming the third country to put a man in orbit.

"India will certainly participate in the US initiative because we don't want to lag behind in the exploration of space," Indian Space Research Organisation (ISRO) chairman Madhavan Nair told AFP, a day after Bush outlined his vision at NASA headquarters in Washington.

"We'll firm up our plans for space exploration afer bilateral discussions with them," he said.

Bush's plan is to send American astronauts back to the Moon as early as 2015 and establish a lunar base that would be a springboard for a voyage to Mars, for which he set no deadline.

India is emerging as a power in satellite launches and last September set the goal of sending an unmanned probe to the Moon by 2008.

In contrast, Japan said it needed further details as to Bush's scheme, which has already run into flak among some domestic US critics as to its scientific value and financial cost.

"I think there will be further adjustment in the United States about this plan and after it is finalised, I think we will then begin to study it," said Hiroaki Sato, spokesman of the Japan Aerospace Exploration Agency (JAXA).

Japan's own space ambitions have been dogged by technical problems and budget constraints, which in turn have been exacerbated by dramatic cost overruns to build the US-led ISS.

Japan is already a hefty contributor to the ISS, having contributed some 330 billion yen (3.1 billion dollars), or just under one-tenth, of its startup costs.

In Paris, the European Space Agency (ESA), whose already strained budget has also been affected by the ISS cost debacle, was similarly circumspect.

ESA Director General Jean-Jacques Dordain hailed Bush's proposals as "a great and good piece of news" that encouraged a timetable for moving beyond orbital missions and towards a more adventurous frontier.

But, even as he lavishly praised the long history of great collaboration between ESA and NASA, he refused to say how far or even if the Europeans would take part in the Bush blueprint.

The two agencies have a great record of working together for scientific success, but in the past two years their relationship has been dogged by friction over the ISS, where Europe, like Japan, is a junior partner, providing a scientific module, robot supply vehicles and crew.

Analysts said European doubts lie on Bush's emphasis on an early resumption of manned flights to the Moon and the establishment of a big lunar base that, putatively, would look for minerals and energy sources, build a spaceship and launch it.

That contrasts starkly, in cost terms, with ESA's own idea of using cheap robots to explore the Moon and Mars by 2015, then proceed to manned lunar missions that would essentially serve to test technology and train astronauts, before finally taking part in an international endeavour to put humans on Mars by 2030.

In Moscow, meanwhile, Russia proudly pointed to its glorious record of space exploration and hinted it was mulling a return to the Moon and Mars by Russian spacecraft, but left unsaid as to how it might raise the rubles to do this.

"We have many initiatives from researchers on organising expeditions to the Moon and Mars," said Nikolai Moiseyev, a deputy director of Rosaviakosmos space agency.

"Before the end of the year, we intend to develop a federal space programme until 2015 and it is possible that such projects would be included," he said.

SPACE.WIRE