President Donald Trump formally announced last night that he is sending Americans back to the moon.

Nearly half a century after the last human being set foot on the lunar surface in 1972, Mr Trump said the moon would be used as a stepping stone to a Mars landing.

He signed "Space Policy Directive 1" which ordered Nasa to "lead an innovative space exploration programme to send American astronauts back to the Moon, and eventually Mars".

As he signed the directive at the White House, with Buzz Aldrin present, Mr Trump said: "We will not only plant our flag and leave our footprints, we will establish a foundation for an eventual mission to Mars, and perhaps some day to many worlds beyond.

"The pioneer spirit has always defined America. This is a giant step toward that inspiring future and reclaiming America's proud destiny in space."

He added: "Space has so much to do with other applications. including military applications.

"Lift our eyes up to the heavens and once again imagine the possibilities waiting in those big beautiful stars if we dare to dream, and dream big. That's what our country is doing again."