The German followed Nelson Mandela, in 1994, in being bestowed the honour for his work at the football club and support for local charities.
"I have to be honest, when I first heard this news I had to take a minute to take it in. As you can imagine, I get a lot of different types of news in my job but this was definitely a 'wow' moment," he said.
"To get this kind of recognition is incredible. It is also very humbling.
"Obviously, I am not from Liverpool so there will be countless people who know more about the history than I do but I actually already knew a little bit about this award.
"This was because earlier this year it was granted to Andrew Devine (the 97th Hillsborough victim who died last year), someone who we all had an enormous amount of love for, along with the other 96 victims of Hillsborough.
"I also know that Sir Kenny Dalglish has received the Freedom of the City previously so if my name is listed alongside those and all of the other recipients that makes the honour even more special.
"So, to everyone who made this possible - thank you. You have made my family and myself so proud to know that the bond we have with this wonderful city has been made even stronger and will now stay for ever."