US space agency Nasa will fast-track plans to build a nuclear reactor on the Moon by 2030, according to US media.
It is part of US ambitions to build a permanent base for humans to live on the lunar surface.
According to Politico, the acting head of Nasa referred to similar plans by China and Russia and said those two countries "could potentially declare a keep-out zone" on the Moon.
But questions remain about how realistic the goal and timeframe are, given recent and steep Nasa budget cuts, and some scientists are concerned that the plans are driven by geopolitical goals.
Nations including US, China, Russia, India and Japan are rushing to explore the Moon's surface, with some planning permanent human settlements.
