The Trump administration has asked Congress to increase NASA spending next year by an extra $1.6 billion as a "down payment" to accommodate the accelerated goal of returning Americans to the surface of the moon by 2024.
The increased funding request comes nearly two months after Vice President Mike Pence declared the objective of shortening by four years NASA's previous timeline for putting astronauts back on the moon for the first time since 1972.
Mr Trump made the NASA funding pledge on Twitter.
"Under my Administration, we are restoring @NASA to greatness and we are going back to the Moon, then Mars. I am updating my budget to include an additional $1.6 billion so that we can return to Space in a BIG WAY!," Mr Trump tweeted on Monday.
NASA previously aimed to return crewed spacecraft to the lunar surface by 2028, after first putting a "Gateway" station into orbit around the moon by 2024.
The newly accelerated goal - an endeavour likely to cost tens of billions of dollars - comes as NASA has struggled with the help of private partners to resume human space missions from US soil for the first time since the shuttle program ended in 2011.
The proposed increase would bring NASA's total spending level for the 2020 fiscal year to $22.6 billion.
The bulk of the increase is earmarked for research and development of a human lunar landing system, according to a summary provided by NASA.
NASA Administrator Jim Bridenstine called the revised funding request a "down payment of confidence" from the White House.
"Our goal here is to build a program that gets us to the moon as soon as possible," Bridenstine told reporters on a telephone conference call late on Monday.
The US Apollo program, NASA's forerunner to the effort at returning humans to Earth's natural satellite, tallied six manned missions to the moon from 1969 to 1972.
So far, only two other nations have conducted controlled "soft" landings on the moon - the former Soviet Union and China - but those were with unmanned robot vehicles.
NASA officials said they would turn to private companies such as Lockheed Martin, Boeing and Jeff Bezos' Blue Origin for proposals on the design of Gateway and the human landing system.
Bezos, the richest person in the world and founder of Amazon, unveiled last Thursday his space company's mock-up of a lunar lander being built by Blue Origin.
