The US space agency (Nasa) has formally outlined its $28bn (£22bn) plan to return to the Moon by 2024, the BBC reports.
As part of a programme called Artemis, Nasa will send a man and a woman to the lunar surface in the first landing with humans since 1972.
But the agency’s timeline is contingent on Congress releasing $3.2bn for building a landing system.
Astronauts will travel in an Apollo-like capsule called Orion that will launch on a powerful rocket called SLS.
Speaking on Monday afternoon (US time), Nasa administrator Jim Bridenstine said: “The $28bn represents the costs associated for the next four years in the Artemis programme to land on the Moon. SLS funding, Orion funding, the human landing system and of course the spacesuits – all of those things that are part of the Artemis programme are included.”
But he explained: “The budget request that we have before the House and the Senate right now includes $3.2bn for 2021 for the human landing system. It is critically important that we get that $3.2bn.”