Brendan Rodgers has sent scouts to watch the forward in action this season, and has been impressed by performances which have seen him net four goals in 16 Serie A appearances.
Manchester City have also been linked with the Spanish-born Senegalese forward, who has admitted he would be interested in a move to England in the future.
However, the player’s agent Ulisse Savani claims the Reds would have to fork out £12.5million to secure his signature.
Ulisse Savini told Radiosei: “If he was to leave Lazio, we will never find a club in Italy that will buy him, assuming the important figures that [Lazio president] Claudio Lotito would ask for.
“How much is he worth? If a say a price Lotito will contradict me. But at present, according to my judgment, he cannot be worth less than €15million.
“I think Keita would be fine with a future in English football. I think that it is much better there than in Germany, for example.
“We have a contract until 2017. It is obvious in the football business around the world that it is normal to receive attention from some foreign teams every weekend.
“I honestly do not know what will happen in a year, but it is clear that the boy cannot continue to have this contract.
“But I have also learned not to be in a hurry. Previous experiences with Lazio have taught me you must be patient.
“There will be availability and a desire from both parties to sit at the table. It is just a matter of timing and I do not think that will be a problem.”
Keita was signed for just £250,000 from Barcelona in 2011.