Jurgen Klopp insists he is "not stubborn" when it comes to bringing in new Liverpool players but remains confident in the ability of his current squad.
Liverpool were beaten 3-0 by Brighton and Hove Albion at the weekend in a performance Klopp described as the worst he has witnessed during his coaching career.
The Reds, who won a domestic double last season and fell just short of an unprecedented quadruple, are ninth in the Premier League and now 10 points adrift of the top four.
Klopp has already added Cody Gakpo to his squad this window in a deal that could rise to £44million (€50m), but he recently ruled out more signings for the sake of it.
Having grown frustrated at the line of questioning at his pre-match press conference ahead of the Brighton game, Klopp was again tetchy when speaking to reporters on Monday.
"It must be a language issue that you ask this question again and again," he said when probed on potential incoming activity.
"We look outside. It's not that we are stubborn and think we will go with these boys until 2050. That's not how we see it, it's all about what you can do and what you want to do.
"It's always each year the same. It should be boring from your side, the transfer window in each press conference. Whoever comes from your agency asks this question.
"I cannot change my answers. If the solutions for us are out there, available and doable, of course we would bring in players to help.
"But we have an existing squad as well, and we are underperforming definitely. But I cannot sit here all the time and blame everybody else, it's my responsibility that they perform.
"That's my first concern. Yes we have limited options, but we have players with a contract here, they are just unavailable.
"If they are all in, it's a different situation. Our squad is not too small. Yes, we have to strengthen, but is this the right moment for us to [sign a player]? I can't see it."
Liverpool are winless in three matches this year, a run that includes a 2-2 home draw with Wolves in the FA Cup third round.
The sides are set to face off at Molineux in a replay on Wednesday, and Klopp suggested he will name as strong a line-up as possible.
"We go as strong as we can, but it always depends on the situation we're in," he said. "Not all of the players who played the last game are available now, for different reasons.
"Yes, we'll make changes. We want to win the game so we obviously need fresh legs.
"The easy thing for me is to tell the boys, 'you put us in a situation with the game at Brighton, let's see how you can get us out of that.' But I just can't do that."