The trio have been granted an extended break away from the club following their exploits at international level for their countries at the start of the summer.
Alisson and Firmino were both involved in Brazil’s Copa America triumph, while Salah was in action for Egypt at the Africa Cup of Nations.
Liverpool FC fans will be eager to see the trio return to action as soon as possible, as they are widely regarded as three of the Reds’ top players.
And Klopp has now revealed that they should be back with their squad when they travel to France for their pre-season camp later this month.
Speaking in an interview quoted by Sky Sports, Klopp said: “Mo and the Brazilians will come for Evian.
“It means then we have nearly a week until City [in the Community Shield], a strong 12 days until Norwich and then 15 or 16 days until Chelsea [in the Super Cup].
“We have to see. The good thing is, when you have a short break you don’t lose a lot. They needed three weeks and so we told them [to take it], but they train now again already.
“I would have preferred it if they had come back after a week, but that would make absolutely no sense! So, [they have] these three weeks and then we will have them here for pre-season.”
Sadio Mane is set to feature in the Africa Cup of Nations final when Senegal take on Algeria on Friday.
“With Sadio, we have to see about him after the final – how he is feeling and stuff like that,” Klopp added.
“It will be really difficult. Sixteen days before we play City, his season is finished. We will have to make a decision, but we haven’t made it yet.”
Liverpool FC will kick off their season with a Community Shield clash with Manchester City at Wembley on 4 August.
The Reds are aiming to go one step further in the Premier League this season after they ended up in second place a just a point behind champions Manchester City last term.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news