The US is planning to build a nuclear reactor on the Moon as it seeks to push ahead in the space race.

Sean Duffy, the new Nasa head, is preparing to announce plans to install a small reactor on the moon to allow astronauts to undertake lengthy missions on the lunar surface and pave the way for future Mars expeditions.

A directive from the space agency, seen by The Telegraph argues that a reactor is necessary to stop rival superpowers effectively colonising the Moon and establishing US “keep-out” zones.

China and Russia previously announced a joint effort to put a reactor on the Moon by the mid-2030s, it notes.

“The first country to do so could potentially declare a keep-out zone which would significantly inhibit the United States from establishing a planned Artemis presence if not there first,” the directive says, referring to existing plans to explore the Moon and prepare for missions to Mars.

Nasa needs to “move quickly” to “support a future lunar economy” and “strengthen our national security in space”, it adds.