Keita will swap the Bundesliga for the Premier League in 2018-19 after Liverpool agreed a deal with Leipzig for the Guinea captain at the start of the season .
The 23-year-old has impressed this term, scoring six goals and tallying five assists for Leipzig, and Klopp is excited by Keita's imminent arrival at Anfield.
"Naby has the quality to have a big effect on the team immediately [when] he arrives," said Klopp, who is looking to bolster his squad following Philippe Coutinho's move to Barcelona, while there is uncertainty over Emre Can's future amid interest from Juventus.
"He is not playing the World Cup so he will have a full pre-season with us, which will help him a lot. We will probably sign a couple more players in summer because we need more depth in the squad.
"To bring in players who are 200 per cent better than what we have will be difficult but we had a problem when Coutinho left and Adam Lallana and then Emre Can became injured.
"You can never remove all injury risk and the boys still did brilliantly, but of course we will try to strengthen the squad because that's how it is."
Liverpool, who are preparing for the Champions League final against holders Real Madrid May 26, face Chelsea in a key Premier League clash at Stamford Bridge Sunday .