President George W Bush will announce proposals next week to send Americans to Mars, and back to the Moon.
Senior US officials say he will also reveal plans for the construction of a permanent lunar space station.
Mr Bush intends to reinvigorate the US space programme following setbacks, including the Columbia shuttle disaster, the officials report.
The manned mission to Mars - where Nasa successfully just landed a probe - is not expected for at least 10 years.
Correspondents say Mr Bush had been expected to propose a bold new space mission as part of his re-election campaign.
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