Firmino, whose contract expires in June, has helped Liverpool win the Champions League, Premier League, FA Cup and Club World Cup among other major honours since joining them from Hoffenheim in June 2015.
"Surprised? Yes, a little bit - it could go two ways and it went one. And I respect that a lot," Klopp told reporters on Friday. "But it's completely normal in this kind of long relationship that we have and Bobby has with the club.
"He told me and then the only other thing he said is, 'Now I want to bring this wonderful story to a positive end'."
Firmino has scored 108 goals in more than 350 games in all competitions and was part of a potent attacking trio with Mohamed Salah and Sadio Mane, who left for Bayern Munich last June, that helped Liverpool win the 2019-20 league title.
"Sadio, Bobby and Mo together were for quite a while one of the best front three in world football," Klopp added.
Firmino scored seven times in 13 Premier League games before the World Cup break but missed two months following the restart after sustaining a calf injury and has been restricted to five substitute appearances since his return in February.
He came off the bench to score Liverpool's final goal in last Sunday's 7-0 hammering of rivals Manchester United.
"I loved the reception he got when he came on against United," Klopp said. "He is completely here and completely committed, and that's all we need to know.
"There's no time for a goodbye or whatever in this moment, there's enough time for that later in the season. He's one of these players that even when he would come with an opposition team, people would be really happy to see him."
Liverpool, fifth in the league with 42 points, travel to bottom club Bournemouth on Saturday.
