Liverpool's form has suffered badly since Mane departed for the tournament in Gabon, with the Reds' only win in his seven-game absence coming in an FA Cup replay against League Two side Plymouth Argyle.
That run has seen them dumped out of both domestic cup competitions and fall 10 points behind Premier League leaders Chelsea, who they host on Tuesday.
But while a quick return for Mane might provide a boost, Klopp – whose side were beaten at home by Championship outfit Wolves on Saturday to make it three home losses in succession – needs to "look into his eyes" before finalising his line-up.
"Ray Haughan [team administration manager] and our team management did an outstanding job to bring him back as soon as possible and he is now on his way," said Klopp on Monday, with Mane having missed the decisive penalty in Senegal's quarter-final loss to Cameroon on Saturday.
"We had the plane there, but he was not allowed to go in the plane and we had to wait to get him from A to B. I spoke to him and it is all good so far. We will be in tomorrow morning and I will make a decision. I will have to look into his eyes and see if it is possible.
"He's a quality player and it's easier when you have him around the team, but you can't expect him to decide games by himself."
Klopp: "Stay positive. There's no reason for anything else. In the short-term, against Chelsea, it would help a lot." pic.twitter.com/QzBVsrJMcZ— Liverpool FC (@LFC) January 30, 2017
Despite Liverpool's alarming slide, Klopp sought to deliver an upbeat message to the Anfield faithful ahead of Chelsea's visit, with securing a Champions League qualification spot still a possibility this season.
"It's very important we build on the good things," said the German.
Perhaps referring to recent suggestions Liverpool's season is effectively already over, he added: "[Are we] allowed to go for the best position in the Premier League?
"It's possible we could qualify for Champions League. Would it be allowed to celebrate a position like that in such a strong league?
"There's still a lot to go for. We should try rather than judging players and talking about our mistakes. We are fourth in the league.
"Stay positive. There's no reason for anything else. In the short-term, against Chelsea, it would help a lot."
Liverpool won at Stamford Bridge in September, which remains Chelsea's only home loss this season.