Japanese startup ispace assumed failure in its attempt to make the first private moon landing on Tuesday as engineers struggled to regain contact with the company's Hakuto-R Mission 1 (M1) lander long after it was due for a lunar touchdown.

"We lost the communication, so we have to assume that we could not complete the landing on the lunar surface," ispace Chief Executive Takeshi Hakamada said on a company live stream, as mission control engineers in Tokyo continued to try regaining contact with its lander.