First-choice goalkeeper Alisson suffered a suspected hamstring injury during the closing stages of Saturday's 1-1 draw against title rivals Manchester City in the Premier League, while Portuguese forward Jota had to be replaced by Luis Diaz after sustaining a muscle problem early in the second half at the Etihad Stadium.
Neither player will be fit for Thursday night as Liverpool return to Anfield in a bid to qualify for the Europa League knockout stages with a game to spare against Austrian side LASK, with Klopp confirming that Alisson's injury is not as serious as first feared but still "bad enough".
It seems that the Brazilian will also likely miss the forthcoming league games against Fulham, Sheffield United and Crystal Palace, but could be back in contention for the home clash with fierce rivals Manchester United on December 17.
However, Jota's issue is more serious and it remains to be seen exactly when he will be fit to return.
"Both are out," Klopp told reporters at his pre-LASK press conference on Wednesday. "With Alisson it is a bit lesser so we will have to see.
"He's not going to play tomorrow or on Sunday, probably not the week after, then he could be kind of OK, but Diogo will take a little bit longer.
"We don't know exactly how long but it is a bit more serious."
In addition to Alisson and Jota, Liverpool remain without left-back Andy Robertson after shoulder surgery, while midfielders Thiago Alcantara and Stefan Bajcetic are also still sidelined.
Klopp said he would pick a "team with fresh legs who want to go for it, enjoy the game and will really fight for a result" against LASK, calling on the Anfield crowd to play their part as they enter a particularly intense period in the season.
He also confirmed that Caoimhin Kelleher would start in place of Alisson against LASK as the Republic of Ireland international bids to prove himself a worthy deputy across all competitions in the weeks ahead.
"He would have played anyway and deserves his opportunity to get a few more games and hopefully he can show his full potential," Klopp said.