Jota went down with a calf injury in the dying embers of Liverpool's 1-0 win over champions Manchester City at Anfield on Sunday.
The 25-year-old has made eight appearances for Liverpool this season, recording five assists.
Liverpool manager Jurgen Klopp has announced that the former Wolverhampton Wanderers man will be out for 'months', ending his hopes of featuring at the Mundiale.
"It's really not good news. Yes, he will miss the World Cup," Klopp said in a press conference on Tuesday.
"It's a pretty serious injury, calf muscle. Now we have to recover. The process starts like this. That's the first diagnosis which was pretty clear.
"It's very sad news for the boy, for us, and for Portugal."
"I don't want to put a number on it. Yes, it will be long."
"It's Diogo and he's surprisingly OK, so far. He's an incredibly smart boy and very reflective. I think he knew it when we carried him off the pitch," Klopp added.
"When I came out we passed each other after the game and he expected what happened. I think in that moment he knew it was a serious one and could be pretty impactful on his World Cup dreams."
Jota has scored 10 goals in 29 caps for Portugal, who begin their World Cup campaign against Ghana on November 24 and will also play Uruguay and South Korea.
