Virgil van Dijk, Fabinho and Curtis Jones were all cleared to return to training on Christmas Eve, following the end of their seven-day isolation due to COVID-19.
Van Dijk, Fabinho and Jones all tested positive for Covid prior to the Newcastle clash on December 16, with government guidelines stipulating a seven-day quarantine.
The trio were then required to provide negative lateral flow tests on the sixth and seventh days of their self-isolation, which were on Wednesday and Thursday.
With none of their results returning positive, and no symptoms shown, they were then given the all-clear to return to Kirkby for training.
They were part of the group put through exercises on Christmas Eve, with Liverpool now able to extend their preparations for the trip to Leicester on December 28.
Due to a rise in cases in the Leeds squad, the Boxing Day clash at Anfield has now been postponed, at least allowing Klopp and his players more time to train for a second consecutive meeting with the Foxes.
Ahead of Christmas Day, the first team posed for a photo on the pitch at Kirkby, with Van Dijk, Fabinho and Jones all present.
It is likely they will be eased back into training, but it would be no surprise if Van Dijk and Fabinho were in contention to start against Leicester.
Jones could be given more time to get back up to speed, having not featured for Liverpool since the 2-2 draw with Brighton on October 30 due to an eye injury and then Covid.
Thiago remains absent, with his quarantine due to end on Boxing Day, while there was no sign of Joe Gomez, Naby Keita, James Milner or the injured quartet of Harvey Elliott, Divock Origi, Nat Phillips and Adrian.
Nothing should be read into the absences of Gomez, Keita or Milner yet, with it likely they are in recovery following the League Cup win over Leicester.
However, there is an ongoing chance of players testing positive for Covid upon their arrival at the training ground, with negative lateral flow tests required before entry is granted.
Goalkeepers: Alisson, Kelleher, Pitaluga, Davies
Defenders: Van Dijk, Matip, Konate, Alexander-Arnold, Robertson, Tsimikas, Williams, Beck
Midfielders: Henderson, Fabinho, Oxlade-Chamberlain, Jones, Morton
Forwards: Salah, Mane, Firmino, Jota, Minamino