Jurgen Klopp has said Liverpool are keen to reinforce the squad in the January window but have been frustrated by clubs' refusal to do business in mid-season.

Klopp has previously played down the idea of January arrivals and said English football is "obsessed" with transfers, but he acknowledged after Saturday's surprise 3-2 loss to Swansea City that the club have been looking at potential additions.

"I understand it is absolutely normal that people ask whether we should have brought players in," he told reporters. "The situation is yes, on the one side pretty simple, but on the other hand it is pretty difficult.

"It is not that we don't want to bring players in -- we do -- but the thing is, the players we want because we think they help us, the clubs don't sell. It is not about money in this situation, it is the winter transfer window.

"Clubs are saying: 'No, we have half a year to go. We cannot find another player like this. We prefer to take money in the summer than a few pounds more in the winter than whatever.' So it is pretty easy. You see the situation.

"It's tight, it's close, we know that, but if the right decision is not possible in signing the right player then you cannot make the wrong transfer."

The Reds, chasing a first title since 1990, have endured a difficult start to 2017, taking only two points from three league games and have now fallen to fourth, 10 points behind leaders Chelsea.

Their only victory since the turn of the year came in an FA Cup replay against League Two side Plymouth Argyle.

Klopp added: "It is not as if there are 20 players out there who could make this team stronger, who are running around and are available. That is the situation.

"That is why I say we know the situation, we are prepared to move, but for the right player. We are not the only side who can decide the outcome of that, though, are we? The selling club makes the decision too."

Liverpool have lost Senegal international Sadio Mane while he competes in the African Nations Cup, while Cameroonian defender Joel Matip missed two games amid uncertainty over his eligibility after he declined to take part in the tournament. FIFA has since ruled that Matip is free to play.