Salah, Liverpool’s leading scorer in all competitions this season, sustained a head injury in the Reds’ 3-2 victory over Newcastle United on Saturday.
The Egypt forward had to be taken off on a stretcher in the 73rd minute, with his replacement Divock Origi scoring the winner 13 minutes later.
Speaking ahead of Barca’s trip to Anfield, Klopp confirmed Salah had suffered a concussion but will be fit for Sunday’s decisive final-day Premier League clash against Wolves.
Firmino, meanwhile, missed the Newcastle clash with an ongoing groin problem, and will remain on the sidelines as Liverpool looks to overturn a 3-0 deficit.
“Both are not available for tomorrow,” Klopp told a news conference. “[With Salah] it’s concussion so he wouldn’t be allowed to play. That’s it.
“He feels okay, but it is not good enough from a medical point of view. That’s all. He’s desperate [to play in] everything, but we cannot do it.”
When asked if Salah will be available for the weekend, Klopp replied: “Yes.”
Luis Suarez and Lionel Messi put Barca in control of the tie at Camp Nou on Wednesday, with Salah hitting the post late on.
Liverpool responded with a hard-fought 3-2 win at St. James’ Park, moving back to the top of the Premier League, with Manchester City hosting Leicester City on Monday.
It was a result that means the title will be decided on the final day of the season, when City travels to Brighton and Hove Albion as Liverpool takes on Wolves at Anfield.
