Midfielder Oxlade-Chamberlain sustained cruciate ligament damage when going in for a tackle during their Champions League semi-final first-leg win over Italian side AS Roma at Anfield in April. The 24-year-old underwent surgery eight days later.
"We're preparing this season knowing he will not be with us on the pitch for competitive matches for the majority of it. If we do see him back this season it will be a bonus," Klopp told the club's website.
"It feels like now is an appropriate time to tell people that for Ox this coming season will be about focusing on recovery and rehab. We've known this from pretty much the day after he got the injury and after the successful surgery, we were sure of it."
Jürgen Klopp has revealed the expected length of @Alex_OxChambo's injury lay-off and detailed the agreed approach taken to his rehabilitation by the club, player and manager: https://t.co/f3xuydnqir pic.twitter.com/jhki1xRVeP— Liverpool FC (@LFC) July 18, 2018
The former Arsenal player scored five goals and provided eight assists in his debut campaign at Anfield before suffering the injury that also ruled him out of contention for England's World Cup squad.
The midfielder also missed the 2014 World Cup and the 2016 European Championship due to injury and Klopp said there would be no rush to get Oxlade-Chamberlain back on the pitch.
"It is so important -- because of how valuable and important he is to what we are looking to do here in the coming seasons -- that the focus is on doing this right and not rushed. Ox is completely on board with this approach," Klopp added.
"I cannot wait to have him back with us for matches, but we will wait for him and we will show the patience that is required to make sure he comes back ready to continue where he left off: as one of the most outstanding performers in European football in that moment."
Liverpool have signed Naby Keita and Fabinho to bolster their midfield ahead of the new season as well as versatile forward Xherdan Shaqiri. Liverpool host West Ham United in their league opener on Aug. 12.