In the Cold War sci-fi classic, “The Day the Earth Stood Still,” a flying saucer lands on the National Mall so a representative of galactic civilization can warn us that our warlike ways are endangering the universe.

Played by distinguished actor Michael Rennie, the alien ambassador, Klaatu, said humanity faced drastic consequences if we didn’t reform.

Rennie had a robot, Gort, to do his bidding, and “Klaatu barada nikto,” one of his cryptic commands, is a sci-fi catchphrase to this day.

The Earth was saved by the kindness of a woman played by Patricia Neal, whose care for Klaatu convinced him not all humans were warlike. For a brief time Monday, life appeared to be imitating art, as a U.N. diplomat from Malaysia was reported in the British press to have been designated as the official human ambassador to galactic cultures — should any ever choose to present themselves to us.

Mazlan Othman, 58, a female astrophysicist who heads the U.N. Office of Outer Space Affairs, was the rumored point person for humanity. That would appear to be the job for which the title “ambassador at large” was invented.

Sadly, however, the story was merely a rumor, denied by Othman when she was tracked down.

It’s too bad, in a way. One can think she would be a better representative than most national leaders.

And we might have had a chance, at long last, to find out what “Klaatu barada nikto” really means.