The 22-year-old put pen to paper on a five-year deal on Tuesday evening after the Reds agreed a £4.7m deal to sign the Mainz shot stopper.
I know he will add to the quality we have in this position
Karius, who previously played for Manchester City’s youth team, has kept 29 clean sheets in two seasons in the Bundesliga.
The Germany Under-21 international has been handed the number one shirt as Karius looks to rival Simon Mignolet for a starting spot.
And Klopp, who was appointed as Brendan Rodgers’s successor in October, lifted the lid on why Liverpool have signed the highly-rated goalkeeper.
“I am delighted we have signed Loris, he has had a fantastic season with Mainz and has developed into a very good goalkeeper since his return to Germany,” Klopp told Liverpool’s website.
“I am really pleased that we were able to move so quickly to get him and that Loris has shown such a desire to come to Liverpool with a lot of other clubs interested in him.
“I know he will add to the quality we have in this position and I look forward to working with him and all our players when we return for pre-season.”
Liverpool conceded 50 times in 38 Premier League games in the 2015/16 season.
The Reds lost 3-1 to reigning champions Sevilla in the Europa League final on Saturday evening.
The 18-time English champions finished in eighth place in the Premier League table after a poor end to the season.
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