The 24-year-old scored his second goal of the tournament in Thursday's 2-0 win over Zimbabwe to secure Senegal's second win in a row and a place in the second round.
Klopp is thrilled to see the pacy forward continue his excellent form for this season but could not hide his frustration that he will remain unavailable for Liverpool for at least a little longer.
"I wrote to him and said 'I'm happy for you, but on the other hand, I could really kick your... lower back," Klopp told a news conference on Friday.
"Of course, they're through, it's good, he scored again and played good again. Mixed emotions would be the best description. As long as he's fit, we'll take it like it is and support Senegal."
Joel Matip also remains unavailable for selection as FIFA has yet to decide on whether the defender should be allowed to play for his club while the finals in Gabon are ongoing, after having rejected a call-up from Cameroon.
"No, I don't have an update. FIFA mentioned it would be a kind of D-Day. But nothing yet," Klopp said.
"We knew about the Africa Cup of Nations before. All teams knew about it. The Matip case is special for us and of course we don't think it's fair. It's another experience, actually, which we don't need. But you have to learn from it.
"I have respect for all they're doing there under most difficult circumstances. It's a great tournament. In the middle of our season makes it not too cool but I don't think too much about it."
Liverpool take on Swansea City at Anfield on Saturday looking to halt a run of two straight draws in the Premier League and Klopp admits that media scrutiny on every match is beginning to increase the pressure on all teams.
"The interesting thing about the Premier League - and I don't know when it started - is that there are only finals," he said. "Swansea are already playing to stay in the league. We play for whatever.
"But each game, especially in your opinion, decides the whole season. That's really intense. But we're really looking forward to this opportunity. We're still in the race and that's really good."
Philippe Coutinho made his first start since injuring his ankle in November in the 1-0 FA Cup replay win over Plymouth Argyle on Wednesday and Klopp believes he is regaining some of his sharpness.
"You saw it already, in the few minutes he had in the last games," he said. "We were happy to have the opportunity at Plymouth to give him 60 minutes because even Coutinho can't come back on the pitch at immediately 100 per cent.
"It helps the whole team when Phil is in, everybody can benefit from Phil's skills."