Jurgen Klopp said it is unlikely Liverpool will sign a centre-back in January because of the economic issues arising from the Covid-19 pandemic.
Defenders Virgil Van Dijk and Joe Gomez are out long term and Joel Matip has endured several injuries since joining in 2016.
The Reds manager said: “There might be some clubs with no financial problems.
“But this club was, and always will be with these owners, very responsible with the things we do.”
Liverpool still lead the Premier League but have stuttered in recent games, taking only two points from their past three matches.
They are due to face Aston Villa in the FA Cup third round on Friday but their opponents are dealing with a “significant” coronavirus outbreak at the club.
On the possibility of signing a centre-back, Klopp added: “I cannot say definitely we will not bring one in but it is just not likely because of the situation in the world.
“If the world would be in a normal place, everything would be fine: we won the league, won the Champions League, the club is in the best possible situation and then you have three senior centre-halves injured, is that a situation when you would usually do something?
“Yes, definitely, but we are not in that situation. I don’t know if something will happen or not.
“You maybe could do something but it would be a short-term solution and we don’t have that short-term solution and that is not right because it doesn’t help.”
Klopp has been using defensive midfielder Fabinho in the backline alongside 19-year-old Rhys Williams, with both inexperienced 23-year-old Nathaniel Phillips and midfielder and captain Jordan Henderson also utilised.
The champions lead the Premier League on goal difference from Manchester United, but have 16 fewer points than they did at this stage last season.
- Stream eight live FA Cup third-round games this weekend on BBC iPlayer, the BBC Sport website and app. Find out more here.