Buzz Aldrin
Former Nasa astronaut Buzz Aldrin gestures during a press conference in Geneva - file picture Fabrice Coffrini/ AFP

Nasa must stop wasting time and funds on the International Space Station (ISS) and solely focus on its Mars exploration programme, former astronaut Buzz Aldrin has said.

Aldrin, who was the second person to walk on the Moon after Neil Armstrong, said: "We must retire the ISS as soon as possible. We simply cannot afford $3.5bn (£2.7bn) a year of that cost." The former astronaut was speaking at the 2017 Humans to Mars conference in Washington DC on 9 May.

The Apollo 11 moonwalker, who has been an active supporter of Mars exploration, said if Nasa wants to send humans to Mars by 2033, it should forget about the ISS, an astronaut-occupied spacecraft that has been orbiting Earth since 1998. Instead, the former astronaut recommends such operations be handed over to private players along with other lower-Earth orbit operations.

Although Nasa has handed approval to an array of lower-Earth orbit projects to players like SpaceX, Orbital ATK and Boeing to ferry cargo and crew from the ISS, a chunk of Nasa's budget is diverted to the station. Nasa has spent close to $60bn on the ISS from 1985 to 2015 according to Space Review despite it being a joint venture between various space agencies that include the ESA and the Roscosmos.

Aldrin says more cooperation should be established between the Chinese and US to explore the cislunar area (the space between the Earth and Moon) and dock a base there that acts as a testing ground for Mars operations. China has already drawn detailed plans for cislunar missions and Nasa has also stated that its astronauts will need to dock near the Moon before they can approach Mars.

"Let's be certain that we've developed a sustainable plan to stay on Mars," said Aldrin about colonisation plans. "No flags and footprints this time."

In 2015, Aldrin had revealed that former US president John F Kennedy had originally wanted to go to Mars and not the Moon, but engineers told him the Red Planet was just a "little bit too far".