Astrobotic Technology reportedly said the propulsion system problem threatens the ability of the spacecraft to soft-land on the moon.
We are currently assessing what alternative mission profiles may be feasible at this time.
It might have just 40 hours of life left.
Large G-forces, temperature extremes, and the vacuum of space put components under huge stress.
If its on course for the moon, it will smash into the surface, Thomas wrote.
A second lander from another American private firm from Houston, Texas, is due to launch next month.
Astrobotics contract withNASAfor the Peregrine lander was reportedly valued at $108 million.
The last time the US launched a moon landing mission was in December 1972 with Apollo 17.
Subsequently, Gene Cernan and Harrison Schmitt became the 11th and 12th men to walk on the moon.