The Egyptian star has been sidelined since suffering a twisted ankle during Liverpool's victory over Leicester City right before the international break.
Although he wasn't available for selection ahead of Liverpool's visit to Old Trafford, Klopp is hopeful that Salah will be fit to play Wednesday when the Reds take on Genk in Belgium.
"Mo was not ready. That's how it is," Klopp told Sky Sports, according to Liverpool's website.
"He couldn't train with the team; I don't know where it came from that everybody said he will play. There was pretty much no chance for today. Maybe for Wednesday, we have to see."
Salah has scored four goals for a perfect Liverpool side that has begun the season on an eight-match winning run.