Liverpool’s Covid cases has increased in the latest round of testing, with assistant manager Pep Ljinders joining Jurgen Klopp and other Reds players in the treatment room.
Liverpool requested for the game to be postponed as a result, which has been granted by the EFL.
The first leg of the semi-final will now take place at Anfield on January 13, with the second leg taking place at Emirates Stadium a week later.
"The EFL has been in regular dialogue with the club over the past 48 hours in an attempt to understand whether the tie could proceed but significant developments over this period have resulted in the club reporting an ever-increasing number of COVID cases," a statement from the EFL on Wednesday read.
"Having now fully reviewed the circumstances involved, the League has accepted Liverpool's request after determining, albeit reluctantly, that a postponement was the only option as the club looks to mitigate against the further risk of infection amongst its squad and staff alongside ensuring public health was protected by not travelling from Liverpool to London.
"As a result of the postponement the order of the ties has now changed with the first of the two legs to take place at Anfield on 13 January 2022 at 7.45pm. The rearranged game (now the 2nd leg) is scheduled to be played at the Emirates on 20 January 2022 at 7.45pm."
Liverpool released a statement, which said: "The latest round of testing on Tuesday returned a significant number of positives, including Pepijn Lijnders, who was due to take charge of the Reds at Emirates Stadium.
"The outbreak has left Liverpool without a sufficient number of players and staff to fulfil the contest as originally scheduled.
"Liverpool Football Club would like to place on record its thanks to the EFL and Arsenal for their understanding, as well as supporters of both clubs, as we continue to navigate through this challenging period."
